I want to note here that I am aware that this is something that is not essential to the game, and if an option, won't be considered until way after release. However, since BE aims to add every faction into the game, I wonder if that includes the sub-factions of the imperium ? I would enjoy to see the sisters of battle, aswell as the Inquisition and Imperial guard or the Traitor guard (And any other sub divisions I leave out here to keep the post somewhat short). I guess if I were in charge of this, I would consider making character skins to represent Battle Sisters, Stormtroopers and the like, but I know there is an issue regarding their size, since Space Marines are simply bigger and stronger in terms to 'power level'. However, still curious as to what the team has to say to that question hehe.
From the FAQ: "At launch, there will be Space Marines, Chaos Space Marines, Orks, and Eldar. Tyranids will also be in the game, as NPCs. We aim to release the rest of the races from the universe over the lifetime of the game." https://www.eternalcrusade.com/faq
Yeah, though Imperial Guard probably won't come until way later, because it will be hard to fit them in. And Inquisition can use any Imperial force they wish, so adding them won't change much. Inquisitor as a playable class for PvE can work, but it depends on how much resources they want to dedicate to PvE content.
Well It's easy to say that other imperial forces will come way after the other indipendant factions I think they will add the factions in this order: Tau>Dark Eldar>necron>sisters with inquisitors>imperial guard + mechanicum Tau are many favorites and they are very different to the 4 factions we have So tau 1st Dark eldar next cause their mechanics seem to be easier to realise and they act as evil counterpart to eldar Necrons cause they are the last indipendant faction and they are harder to realise then the other 2 Sis+inqui cause I doubt that inquisition can fill all rolls by them self Imperial + mechanicum they are the hardest to make cause IG are so squishy Mechanicum would mostly fill the vehicle and walker part