GNRFan- Personally, I like the coloring on the first icon best. The men stand out the most there.
Shazza- I really like the cleanness of both the icon and the banner. That said, I feel like both, particularly the icon, are just missing a certain 'umph', if that makes sense. Technically speaking, they are well executed, though I'm not so crazy about the crop on the icon. That said, everyone likes different kinds of crops, and I tend to go for the ones that are more extreme and that follow the rule of thirds. On that score, I'd recommend pushing Michael a little to either side, so that he finishes or starts at one third (horizontally) of the icon (hope that makes sense). I think it also might help if you cropped it differently so that it cuts off his hat, which, IMO, would help make his face stand out more.
I think that part of the problem is that the black in his outfit sort of overwhelms his face, just because there's so much cloth. That said, it's Michael and it definitely makes sense to include as much of his body and movement as possible since his dance moves were a big part of who he was as an artist.
I guess my big recommendation would be to find some way to push a bit more color into it. I feel like a more worn-out vintagy colored texture would work well at soft light over him. I'd recommend something by chaoticfae or spookyzangel (deviantart). A brush or text or some sort of zap of color (perhaps red) could also work.