I don't think adding or removing units will happen at this stage of the balancing process.
BTW, if you want to try DoW, don't get Soulstorm first, that's buggy out the wazoo, was made by a different developer. Also you need the expansion/game a faction was introduced in to play it, for the original four (SM, Eldar, Chaos, Orkz) that's vanilla DoW, IG needs Winter Assault, Tau and Necron are Dark Crusade and Dark Eldar and Sisters of Battle are Soulstorm. Yes, sounds like a huge ripoff but then again that's 1-2 extra factions per expansion and the original 4 were already plenty, they're sized the same as the factions in other RTSes, they're not just cookie-cutter addons.