I really like the lifestream green for the button, it should merge well with the new theme. Some thoughts:
hexagon shape is hella sexy - reminds me of the original cell/web-like shape that was prominent in AC covers/art. For some reason in some instances, the hexagon with icon over the edge makes the hexagon disappear.
SOLDIER symbol should stay within the shape, not go to the edge/over the edge, it seems to lose the shape as well. Same goes for Shinra I think.
Circle is also good and works well with the icons that bleed over the edge. Smods, Admins, Staff, Donators, Regular Members? It seems like a bit much. ¯\_(ツ)_/¯
There's something sexy about the clean white icons... but that bitching Jenova head can't be lost.
I'm not too sure on the different colours for different levels... how many would there be?
Final thought re: size/icon numbers: could a plugin be installed so that, should a user have more than 3 icons, they can choose which to put on their post bit? Like, for some who are Admins/Smods, also Great Old Ones, Donators, Site Staff and more... Lex for example could have 4 of these icons. I don't think there are as many people like him but there he is
So what if in the user profile it shows all icons.. but when updating a user profile, you could choose which 3 icons you want represented on your post bit area. Or maybe even two. These are such awesome ideas for graphics, it would be a total shame to see them hindered because of size