Calimero, you can never have too much upgrades. I would like some basic upgrade settings by choosing a "class" at the beginning, and then you start with 1 upgrade like engine or shield or cannon or allied units, and one more upgrade is available in that section then as well. also a sandbox and an endless mode would be nice. These are just suggestions, but now after finishing it once it is boring. 4/5
Wackie, the characters have different speeds, speeds when carrying the heaviest weapon, initial money, and they should have different lives as well (but that doesnt seem to work) anyway, that is the difference. for the rest i have to agree that sometimes it would be annoying to kill enemies which are immediately at the ending point. however, I have NEVER encountered ethereal or flying enemies on those maps so far. 5/5 from meh!
 "Fantastic Contraption"){kind=icon}
 "Ether War"){kind=icon}
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 "Epic war"){kind=icon}
 "Elite Forces:Conquest"){kind=icon}