Here are the character silhouettes (I googled how to spell that word. That is a stupid word to try and spell). I think the space helmets help make them a bit more interesting.
I haven't done any colour tests yet, I did these base colours and decided they worked to I'll go back and do some variations. I don't think the final colours will change much from these ones. In the first image the colours are pretty desaturated, so I saturated them and decided they worked better.
Here's the obligatory 'neon' version too. I need to try these on some backgrounds I think.
Feedback is more than welcome!