itch.io

Well, there are plenty of homebrew games (with a good chunk of them being free) out there and several of them are notable, so this is definitely a good move. Also it's not that you can't use Sonic or Mario characters at all, it's just that it's not (legally) recommended to use them in "commercial" projects without explicit approval from Nintendo or Sega. There are plenty of free fangames out there that prominently feature both of these franchises' characters, assets, etc. and most of them haven't been taken down (in fact, in the case of Sonic fangames, Sega has pretty much endorsed them). And I have seen that you are using original characters (or at least generic ones) in games like Boulder Crash for the GBA and DS. I do understand that you may need some money for whatever reason and that you aren't just doing this out of greed. Keep devving homebrew games!