The best person to ask that is Daniel McNeely, so you should leave a comment on his profile. And he'll probably have to run it by Nitrome since it's their logo. But I agree, it'd look good in other colors.
Out of all the available images to use as armatars, what we have here is a "nitrotar". One nitrotar is fine among dozens upon dozens of armatars, but 10 different nitrotars could destroy the entire armatar system; half the site would just be wearing red or blue or whatever colored nitrotars. It wouldn't represent AG anymore; we'd just be one giant Nitrome ad.
