This is tailor-made furfag fuel.
I hate custom character bullshit in narrative games. Sonic Generations's story was the least it could be to provide a setting while remaining at least somewhat decent, so it's not like there's a lot of story to ruin with this game. Still, this made-up bullshit is going to interact with the likes of the legendary Sonics, and nothing that anybody creates will be canonical.
I think I've settled it: If I get this game, I'm going to make the most utterly retarded-looking avatar I can conceive--something that looks like a walking mess of garbled geometry. If Sonic Team isn't going to take their game seriously, why the hell should I?