I'm not an artist, but aesthetically all the empires look amazing to me. The level of detail and color choices are astounding for a game of this scale.
A big part of the TR is their love of goggles. It's one of the thing that sets them apart. Also if you don't like the default skins you can buy new ones, but personally I think they look awesome.
I will point out the VS design for their tank is horrible. I've already said more than enough and tweeted the developers about it and Higby said it's basically set in stone already.
I was just going to post an
image but Hamma frowns on that.