Steel legion

I guess it would be wise to have something basic like the new Chimera and the new Guardsmen and maybe the static Heavy bolter in the update so you could play a basic mission and get a taste of what to expect. That it would be wise to keep adding moderate amounts overtime instead of waiting until everything is finished or releasing new stuff every two seconds. No experience in this matter but I do/did used to lurk over the Invasion44 Mod's website and that's how they did things.

I was wondering, would you model an Imperial Commander or some IG Warfare game-mode buildings?

I say you flesh out the imperial guard. Get that baneblade model, finish chimera variants/chimera, add different leman russ models, and give them to the lost and the damned and loyalist guard. add stubbers, and autoguns, in additon to lasguns, as well as shotguns, and add sentinels with multiple variants.
then get to work on the tau and/or the eldar.

not much then lol

some of the things Dark Knight mentioned may be feasible soon, update as soon as Im allowed to give more details.

Thanks for the input guys.

Well that's going to be quite along time without a playable update if we'd have to wait for them to include all of that in their next update. Which means people could lose interest in the gulf of time or simply just forget that the project is being worked on. If the updates were moderately balanced in both pace and content it could keep fans interested and it could allow players who already have the game to start making missions with the limited assets and then move onto fleshing those missions out or creating bigger and better ones when the units become available.

I would seriously advise against beginning to put all their efforts and hard work into the Tau and Eldar factions at this time while the Space Marines already have work done on them and are in a limited playable state. It would make sense to get them done and out the way to a level before returning to flesh them out. I'd suggest that Chaos should get a look in after the Guard and SM stuff. Purely because I cannot wait to try this mod in Multiplayer with friends of mine and it'd need to be somewhat balanced or to scale.

At the end of the day It's the creators' decision on what they want to do and I eagerly look forward to each update.

also, get weapons teams in!
heavy bolter weapons teams, lascannons, auto-cannons, mortar, etc.

implement plasma guns, melta guns, las-carbines, long-las, hot-shot lasguns, perhaps storm-troopers, elysian drop-troops, valkyries, air units in general, drop-sentinels (yes they are a thing--look on forgeworld IG vehicles),
flamer laspistol, autopistol, stub-automatic, heavy stubber, stub-gun/stub-pistol, stubber

at this point im just putting out general goals.

GUNZ are high on my list after characters i have a bolter, bolt pistol, storm bolter and heavy bolter that all need remodeling and a nice paint job. Some of the other guns are almost ready that you said. The plasma stuff and flamers need a FX configuring for them so that will be "later".

"I would seriously advise against beginning to put all their efforts and hard work into the Tau and Eldar factions at this time while the Space Marines..."

To this i say yes and no, i like to change up. maybe one day I want to paint textures, the next want to sculpt on some Tyranids the next i want to box model a power sword. and that's kinda how we work, if you wanna try something then try it but at the same time we do actually make decision and crack on with it once "tests" are done.

I know that you chaps are struggling for a Map designer, ever thought of using some of the desert maps from AO and adding IG units such as Tallarn?