Stage 1:
normal (bullet) guns, no power guns (lgun)
no light Armour
no battery pack
Oh boy. Let's totally ruin the game. Humans can barely survive in S1 WITH light armour. Let's get rid of it!
Stage 2:
new guns
light Armour
no battery pack
some buildables
New guns? What new guns? splain plz. Please tell me we get helmets. They have goons by now. Without helmets we're fucked. Only some buildables?
Stage 3:
some power guns
helmet
battery pack
2 guns
new buildables
People can barely handle one gun, never mind two guns. You also need to clarify which 'power guns' and buildables.
Stage 4:
with 2500 credits, you can buy a robot armour, with 2800

Aliens:
Stage 1:
normal (dretch) aliens, no dragoon, only dretch and basi.
normal buildables
No dragoon? What about marauder? Only a few people can handle a basi. It isn't easy.
Stage 2:
goon
adv. dretch
some buildables
Adv. dretch? What's so special about this upgrade? Why only some buildables? Do we lose tubes or something? Overman go boom?!
Stage 3:
adv. goon
adv. basi
new buildables
This seems alright. What new buildables?
Stage 4:
tyrant
Okay thus far...
with 11 evos, you can evolve into an adv.tyrant
