Minor nitpick:

The idea that there's a difference in strength between bolters and "Astartes bolters" is absent from GW's version of the setting, and exists solely in some licensed material such as a few novels and FFG's roleplaying game. In GW's own d100-based game, "Inquisitor", both humans and Space Marines get bolters with an identical statline, and Codex fluff flat out mentions for SoB to get "equal" weapons to Astartes, and they are merely human, too, so I see no reason why the bolt weapon carried by a Commissar or an Imperial Guard officer needs to do less damage. On the contrary, it fits better to GW's own material and it makes for easier balancing!

(Though Marine bolters are obviously scaled up a bit to conform to their larger hands. Personally, I'd interpret the size difference by giving the Marine bolters extra armour to better withstand the physical stress of close combat and/or giving them a few more gadgets in terms of internal mechanisms .. just like it works with Space Marine power armour. Either way, they still shoot cal. 75 rounds, which is about as big as contemporary shotgun shells. A Space Marine bolter is essentially a modern day AA-12 with Frag-12 explosive rounds that someone was crazy enough to stick a miniature rocket motor to)

Anyways, hellguns are not so bad. In fact, don't they have a higher armour penetration than bolters? Plus you could give Storm Troopers certain perks to make up for any drawbacks. What if they'd carry a higher number of grenades? Their smaller size alone makes them more difficult to hit, and if you include a clever airdrop mechanic they could be devastating hit&run troops that storm objectives with Valkyrie fire support!

That said, personally I'd only want to see Storm Troopers as part of a larger Imperial Guard faction, and in this case they should obviously be balanced against the rest of their units. Armoured warfare and artillery barrages could be a gamechanger!

Well, it's probably too soon to jump to conclusions! But it certainly is interesting to see that the studio has not forgotten them (anymore).

Haha I wasn't trolling. Guard aren't flavorless, just that in EC I can't see playing as AN Imperial Guardsman as a major draw card for any but a very small group of table top loyalists unless perhaps, it was offered as an alternative to Orks after release (I do like that concept btw). How you'd write IG vs SM is a little tough without some serious writing. I know it was done in the DoW expansion campaigns but in a large conflict like EC, they're natural allies where alliance building appears to be a strat of choice.

So maybe what I should have said is they have the right 'attrition' mindset to rival Nids as starring NPCs, in a renegade fashion at least. And they would certainly be massively painful. Kasrkin be bastards.

The Sisters of Battle are part of Eccleisiarchy so that's a fair point however they are also militant wing of the Ordo Hereticus and much, much, much more likely to have Inquisitors present than any SM chapter represented other than perhaps Ultramarines (particularly DAs, though also BA/SW with their geneseed) even though I admit that wasn't where I was going. I was more conveying my preference for combining the Inquisitorial Chamber Militants into one faction given the choice. No technical reason they couldn't be slotted in right now, nope. Again, having any of the 3 factions at war with 4 founding chapters of the SMs is a stretch to the lore.

I can see the draw of playing as a single guardsman, the liberation of the fact that you don't have to worry about which gun pointed at you is more powerful, they will all kill you quickly so the requisition and unlocks of other factions is rendered meaningless to you, a guardsman dies to a powerfist as fast as he dies to a chainsword to me that makes the resources your enemy spent on the powerfist wasted resources.

I will assume that because of the squishyness of a guardsman his equipment costs will be cheaper than a marine's, so he will get plasmaguns quicker, powerswords cheaper, personal forcefields, static move or fire heavy weapons a lot cheaper than a marine will get one. It's all about tactics and it's fun to play the underdog.

Other factions get mega nobs, terminators, wraithguard spawns the IG spawn can be Ogryns for close combat, sentinels for ranged combat.

There are plenty of options to be had.

I guess it'd also depend on what exactly they'd offer in terms of advantages to counter the disadvantages. If, and that's a big if, IG players would start as Sergeants with their own squad of AI comrades (similar to the "Commander Battle" mode in Mount & Blade Napoleonic Wars), I'd consider that a huge draw! Alternatively, maybe balance their comparatively weaker infantry with easier access to armoured vehicles? This game features tanks, and their usage must be governed by some sort of resource mechanic or cooldown. I could see IG players getting a bonus here.

But I admit, I also really like the idea of having basic Guardsmen as F2P. Perhaps the threat to Ork faction population could be mitigated by the IG being a latecomer?

That's true. Though, wasn't Dawn of War: Soulstorm a large conflict as well?

Personally, I think I'd prefer the Imperial factions as a sort of "loose alliance" where they don't fight one another, but the exact level of mutual support may change. But needless to say, this creates huge problems in terms of balancing the Imperium of Man against its enemies - not only does it have the most fans (by being "the human faction"), it also has the most sub-armies.

Maybe the Tyranids might work as a counter-weight by providing popular PvE content and thus binding a large part of the players. In WoW, the Alliance was the most popular faction, yet the Horde was much more active in PvP. Perhaps this effect could be replicated, thus essentially "splitting" the Imperium into one group of players that will never bother the Orks/Eldar/Chaos/Tau/etc simply because they prefer fighting PvE 'nids...

Ahh, gotcha. Though you should know that a lot of SoB fans prefer the Sisters as the Sword of the Church Militant, rather than seeing it focused on Inquisitorial duties, which is just a sort of part-time job for them.

Also, how would you balance the three Chambers Militant and organise their progression? Grey Knights are arguably more powerful than "Vanilla" Marines, and unlike with the IG they do not offer much in terms of mitigating this fact except smaller numbers (and for some reason I have a feeling this would be the opposite in an MMO where anyone could play them).
In theory, you could weaken their advantages and thus effectively render them Tactical Marines in silver armour, but would the fans stand for this? And then we have the Deathwatch, which (by GW fluff) is essentially just a small black ops unit rather than a full army.

Tbh, I think DW Marines and Grey Knights would work much better as a sort of "hero class" for Space Marines. Basically having players unlock access to a sort of elite circle of specialists where they get to play one of these guys, after having invested a ton of time playing normal Marines.

Just my two cent, though.

I never said speed wasn't an advantage. In fact, your whole post is exactly what I was saying. They're more skilled and faster than the Space Marines, and hence have that advantage over them.

The announced Aspect Warriors do not have this 3+ armour, which is what I was using as a base for that argument.

That said, I can't source it or anything, but I was under the impression that Power Armour > Aspect Warrior 3+ save armour in fluff. Maybe just by a little or something, I dunno.

Perhaps in some sources.
The thing is, once you leave the clarity that is numbers and stats in the TT, you are bound to find a whole lot of conflicting accounts and differing interpretations, simply because that's how the IP works. For an example, see above for my post on how bolters are portrayed in products from different sources.

I'm sure the developers of this game have the same amount of leeway and artistic license that is granted to all Black Library novel authors and FFG's RPG designers. That means if you want to have Marine and Aspect Warrior armour be the same for the sake of balancing, then you can totally make it so.

In fluff, of course Marine PA has certain unique perks such as a medical auto-injector, atmospheric seals, enhanced imaging, a waste recycler, and so on - but then again, those either did not change or are already included in the 3+ save they get ... plus, who knows what "minor perks" the Eldar give their suits!

Definitely Soulstorm was a large conflict but you have 4k of the First Founding legion chapters in open war against 4 of the most well known and best connected Guard armies is a little on the nose. In Soulstorm it was a case of mixed signals for plausibility's sake (and that the Ravens are more than likely sons of Magnus [eye twitch!!]). The same writing problems arise with implementing Sisters or any of the Ordo forces though we agree; been done before.

I see what you mean with DW, in fact other than a better loadout selection they are regular chapter marines with considerable anti-xenos training. Grey Knights as an unlock would be amazing.

'You have ruled this galaxy for ten thousand years. Yet have little of account to show for your efforts. Such failure must be as depressing to bear as it is pathetic to behold.'
-Imotekh the stormlord to marshal Helbrecht during the battle for Schrödinger VII

Making a Warhound Titan move a little slower or do slightly less catastrophic damage is not categorically different from having Space Marines run slower (they don't run as fast in EC as they do in the lore) and not have all of the combat and noncombat abilities associated with their additional organs. Compromises need to be made for game balance on all fronts. If you're saying to me that you think making a Warhound titan interact believably and in balance with the other vehicles in EC is impossible, I will believe you. But considering the relatively small difference in power between a space marine's Vanquisher cannon (which will almost certainly make its way into EC) and a Titan weapon, I think the specific objection to the power/scale of its weapons is overstated.

I would like to see Chaos Daemons ingame, but rather as a part of Chaos, together with Renegades, maybe not even as a playable race.

I voted for IG, acsess to more Tanks at cheaper resources, but increadebly weak in combat.
There are actually a few Factions I DON'T want to see, because (in my opinion) the given factions reflect the feel of Wh40k the best (the 4 oldest races) and they give you the best customisation options.
I personaly just don't feel Necrons in an RPG, neither do I feel Tau in such a gameplay.

Maybe it will blend together as nicely as in the good old Unreal Turnament mod, hopefully