Basically I think the reason bfn didn't get any variants and had more simplified maps is because they wanted it to be competitive. Now my reasoning is because if they wanted the game to be competitive they would have to either a) spend a long time tweaking some variants and ability's to be better balanced or b) (the route they took) just remove variants. Now the only evidence I have for this theory is thunderdome being a competitive 4v4 gamemode but I think there's a tiny bit of truth to it.