Yes, that's one of the changes with the balance mod, that engineers can build roads, very useful!

Its hard to make several battles the first few turns, but obviously depend on the sites available and how the defenders are set up.
If the defenders don't rush you, there is a very good chance you can split them in 2 groups and hence fight 4v2 or even 5v2 and use one unit (preferably cavalry) to bait the other group, and then run away since your movement is greater then theirs. With a few range units in your army, you should be able to get away relatively uninjured. If all go wrong, you can always retreat and try again. Sometimes its enough to surrender or sacrifice 1 unit to "save" the rest of your army, this is when everything else fails obviously! Next turn I will try to show you in my battle for the watchtower.

Dreadnought engineers can build roads? Or do you mean the research that allows your builders to go further/get mountaineering?

I used to go for building hall and then storehouse. Didn't think of getting a lab that early, although naturally the RP are nice. but I feel like I then am too weak to clear sites early and I'm happy when I make it to clear one site a turn, if even. Seems like I'm doing something wrong in these tactical battles How are you able to clear more than one site with the starting army?

Necro should definitely be built into melee units in my opinion. The videos of the games where I play Necro can illustrate more than I could write about how to build Necro heroes. Basically, the strongest and most obvious build is to focus on Ghouling Strike and pick abilities that makes it more successful (I prefer Inflict Despair but Inflict Curse is good too for instance) and of course Raise Cadaver, Lesser Reanimate Undead (LRU) and - if you play Necro or get some stronger Undead units - GRU. Control Undead is good too of course, as there are many Necromantic Circles and Haunted Boneyards.
A spell-focused build can be very good too with Undying Army

Basically, heroes with healing and mind controls are the strongest 1st picks, so Theo is the best, then Necro/AD, and Rogue (no heal but Charm).
The issue with Warlord's Field Medic is that your Leader is always stack's leader so if you want to benefit from it, you need to put your leader out of the main stack (at least adjacent to it), and it's not always convenient.
Sorcerers are very poor first pick for classes and races without healing, like Warlord or Rogue (especially combos like Tigran Rogue or Warlord).
For the 2nd pick, it's totally different and a Sorcerer is very good because of his spells, stack buffs, and Master Illusionist.

I think when to send your hero(es) with their own stack depends on three things: 1/ how aggressive you need to be to put pressure on your opponents/keep a good pace of development, 2/ how many units you have and 3/ the risks of stumbling into a stronger enemy army.
If you need to be more aggressive in your development, it's better to split because two groups on two completely different paths clear twice as fast in theory. But if you have less than 12 units, obviously, you should stay grouped. And if your units are not strong enough to constitute 2 clearing stacks, you should also stay grouped. And then if you know you're very likely to find enemy stacks that are stronger than you if you're split, you also have to stay grouped.
So I will as much as possible do separate groups and use my heroes as stack buffers, but very often, you just can't really do fully separate groups because you need to keep strong stacks together.
My Theo and Dread are usually built as stack leader while when I have a Rogue or Sorcerer, I sometimes focus on building a strong support/melee hero without stack buff abilities even though I could, because Rogues are such good high-level melee units and Sorcerers' spells can be devastating/very useful in manual tactical battles.

Also I should mention that Theo and Necro have two spells that can very significantly help to engage in difficult battles: Slayer's Doubt and Stiffen Limbs.


Then some other starting questions:

RESEARCH
It really depends on the class, specs and what you want to do. I usually have target research that I want to do early game and I try to unlock them first before going for class units. Sometimes I do not even really go for class units as Empire Upgrades or Strategic Spells are better in combination with race units. Combat spells are usually a bad choice because, while they will be great in manual, they may ruin your day in auto-combat. In auto-combat, the AI casts your spells not very cleverly and not really at the best of time so you may end up wasting all your CP in useless spells and your Leader doing nothing but casting spells, while he could be more useful doing other stuff.
Usually my early-mid game targets:
- Dreadnought: definitely the economic Empire Upgrades. Unlocking Engineer can be useful to build roads
- Theo: Martyrs and Exalted Martyrs, though not rushing this strategy and first focusing on some other stuff is also viable. Order of Healing and Produce Evangelist can be good targets.
- Rogue: Produce Bards. Then usually I go for the Explorer's MP upgrades.
- Necro: Whispers of the Fallens (top priority), Stiffen Limbs, Undead Plague, the Empire Upgrades up to Harbinger of Deaths.
- AD: class summons and units and CP seem more important than for other classes in my opinion.

For CP, I usually try to have as many CP as my mana income, not to waste mana and not to lack it.
You also have to optimize research and do research you can achieve in as few turns as possible given your RP (so if you have 100 RP, try to do researchs at less than 100 or at multiples of 100, e.g. 200, 300, etc. and not research at 120 RP).

CONSTRUCTION
When I started I thought only Builder's Hall then Settler was viable but there are actually several good openings. You can build 1 more unit to support your weak army, it can be quite a big boost, but unless you're Human (production bonus) or have a Magma Forge, you're likely to need 2 turns to build it, which is annoying. So I actually almost never build a unit first and usually first do the Builder's Hall then the unit (and most of the time, I actually never build units in the first 10 turns, but that's risky, depends if you can summon stuff too).
Going for a Lab is a good idea as 30 RP is a big difference from 20 RP and reduces by 33% the research time for 60 RP skills. But, especially if playing Dreadnought, you can try to rush the Builder's Hall then do the Lab, it takes less time and costs only 50 or 100 more gold.
A Store House can also make sense, especially when playing Dwarves, because of their high pop requirements to build Settlers.

EARLY UNIT MOVES
I usually look for a Great Farm to get a free unit, which will be very useful to reinforce the weak starting army. I very often scatters my units in all directions in the 1st turn to try to see what's around me and find the closest independent. It's good to have a good idea of what's around to plan the most efficient clearing path. But then you should start regrouping all your units to start clearing quickly and target clearing 1 to 3 sites every turn to get XP and resources.

I can just echo what Fluksen said, very good analysis! To add, a Nero for example, dont need any additional healing, so a spell/melee trong unit such as rogue/warlord or sorceror is very good. They also have skills that suit a necro army (blood brothers, resistance, defense, +1 shock etc etc.). For a Druid, Theo the same applies. For Rogue, Sorceror, Warlord, Dreadnought a healing aura is always nice (Theo/Druid+healing at lvl 2,3 respectively).

Dreadnought is actually one of my favourite heroes (when playing necro, theo, druid) due to the strong melee/defense as well as strong range attack (fire bomb, musket) + resistance, fire, shock leader abilities.

All in all, all classes and heroes have some benefits when playing any specific class, just depend on how you spend the upgrade points!

About Heroes:
If I play something that doesn't have easy access to heal I usually try to get a hero that has a heal ability (Theo, Druid, Dread or Warlord) as first hero, so if any of those show up I'll take it.
As far as longterm investments go I actually always think warlord is the best because it gives so many cool buffs (e.g. defense command, blood brothers and toughness) and you can easily turn it into an absolute killer machine: first strike, tireless and martial arts are all inherent and extra defense and attack are easy to come by itemwise that is what imho makes warlord better than Theo and Necro, they are also really really cool lategame but they start with such bad defense (and in case of necro also resistance) that I always find it quite hard to make them sturdy enough.
Usually I try to have at least 2 heroes that I try to skill towards close combat because it seems most items are meant for that and all the extra melee dmg and defense would go to waste if I keep my hero always out of battle to cast stuff, at least it feels like that
The rest depends on what I'm playing against (e.g. take sorc when playing against dread and vice versa), but in this 4vs4 probably that doesn't matter that much because there will be everything on the battlefield anyways...
But didn't use to play the pbem mod, I think they made rogue and dreads a bit stronger in the high levels so maybe they are the new kings of the hill now, have to check what actually changed for them

@all About hero recruiting:
1.
I used to put all heroes in one army with the faction leader and my strongest units. That means I only needed leader abilities with my leader and the other heroes concentrated on individual development. I guess as soon as you have more than one stack of strong units it is better to separate the heroes but would you separate them from the beginning? Or when/in what cases and why?
2.
Because theocrat heroes are best when leading (at least that's how I feel when looking at the skills), I mostly didn't like to hire them. Anyway: What heroes should be hired and which shouldn't/ in which cases? What classes do you like to hire in early game and why? Should a warlord hire a sorc and vice-versa, to complement each other?

I like to hire rogues in early because they have multiple ranged damage elements and necro because I had the feeling these become very strong melee units given a bit of time. Also, necro heroes do not have a pure physical ranged attack but multiple damage elements unlike many other units/heroes which focus on one.

As it's not an advice that include strategic information about any of the team, I'll share it with everyone.

I strongly advise NOT to take the Cartographer's Tents until ALL your team mates have found their closest independent. In a Large map like this, knowing where is the 2nd closest and cities further afar is very valuable.
There are two camps in the debate about Cartographer's Tents and some prefer to always take them at the start but I believe the case for not taking them immediately in Large maps is even stronger. Gaining a few turns to find your closest independent does not change much in a longer game, whereas finding the 2nd or farther cities is much more difficult in a Large map.

Hello Zytozid

The game is hosted (see details from Hiliadan below) and you are the only one left to join!

/Marcus

@Elysian Yeah I did the same at first, until i noticed that when you join you can just click on the position you want to be in to move there (if its not already taken of course)