could be better if u do this:
-add chosin ur path or somtin so u chose to be allien or predator
-u should have upgrades like plasma caster,piercing blade or better sword and for allien more tail dammage upgrade,to summon things taht suck in ur mouth and make allien in u lolz XD and longer mouth-goin-out-from thingy with teeths XD
-u should add stronger ennemies like armoured predators with guns and saws for allien and allien with predator mutation(if u were watching AVP 2)
or allien who sprays acid or somtin....oh,and last one...
-u should add boss fights with allien queens from all parts