I'd personally prefer individually evolving player Aliens than playing as the entire hive. Earn/unlock biomorphs from various "skill trees" that see your critter molt from a basic Drone into an absolute walking blender, with options for things like spitting, poison attacks etc so it isn't just speed, strength and armour upgrades.
Then again, I prefer AvP mechanics where the Aliens can 1v1 the other factions and have a fair shot, rather than being an endless horde.
For those who prefer the swarm vibe, you could easily have pheromonal upgrades that allow you to summon weak-ish NPC allies that get scarier as you progress that tree (eventually becoming a Praetorian equivalent presumably).