Are these maps all on the same celestial planets? Do they all have the exact same mass? I think the game would feel a little more space-like if they actually varied the gravity like it would in real life across moons and or planets Just saying, its not hard to do since your havoc engine already has a value for it that you can adjust in 2 seconds.
You could argue that they colonised the earth like planets. The smaller ones couldn't hold onto their atmosphere and the larger ones crushed them with their gravitational pull. I'd argue that someone questioning the validity of a game set on another planet with beam rifles, 25 foot robots and jet packs needs to stop sweating the little things
you know, this might sound strange but the lack of variation of gravity is the most phony thing about this game to me. I really think they phoned it in on that and decided to make it like all other FPS games and missed an opportunity to differentiate a little more.