well heres some few suggestions.
1.Team Death-match Game mode = Most kills wins.
2.Homogaunts and Termagaunts as Tyranids start and make warrior an rank which has enhanced speed or resistance.
3.Different races on each map.
4.Faster Bolter fire rate but weaker dmg.
5.Dreadnaught plus HIve tyrant.
6.Better Crosshair for Tyranids ranged units.
HOPE YOU GET THESE STUFF.

People really liked your mod.