The problem is that everyone has a different idea of what constitutes "sick looking." I wasn't there, but I'm pretty sure the art team at Microprose probably thought their designs for the power armor made your soldiers look like the ultimate bad-asses. I'm not sure what they did to damage enough brain cells severely enough for them to think that, but the only alternative is that they were trying to make it look stupid, and no one would intentionally sabotage their source of income.
Power armor has a fairly long history in science fiction. If anything, they both borrowed from Starship Troopers (the original Robert Heinlein story, not the movie) and other sources than from each other.
Presumably for the same reason a rifle scope has a single eyepiece and not binoculars. Most people have one eye that tends to be slightly dominant. That's the eye you use to line up your shot! (In my case, my right eye is the dominant one ... which is kind of sad, since my left eye has better vision.)