I doubt anime cons could agree on unified rules (ICG or not), since each masquerade director has their own view of how the rules should be. Most cons change their masquerade director annually, so with each rotation, the new director may decide to mold the rules to fit his/her ideas.
As for commissioned costumes, I would agree that they should stay out of craftsmanship judging. However, I think I would allow commissioned costumes in skits, if and only if the performance is the only thing being judged, and such awards do not add into the craftsmanship rankings.
I would really prefer the awards specifically target either performance or craftsmanship and rank on those categories separately. There are some people who can make good outfits, and there are some people who are really good actors.
I enjoy seeing good costumes, but I see a lot of skits that don't entertain me.
2012 Convention Schedule
Steampunk Worlds Fair | Otakon