Slappa looks pretty good. I'll give it a try.
I think a street fighter II clone will pretty well define what I was hopping
to find. If you ever decide to make one it'll be awesome. Please let me know
if I can help.
I don't have any experience with MUGEN either, but I'm guessing as you that
they probably use scripts of some sort, hopefully nothing compiled though.
I'll have to investigate about it. Though I do have seen some “open
source” IDS for character development.
If MUGEN characters don't include any compiled parts but readable scripts, I
think that'll be OK for me. Is probably true that most of the characters
created available on the Internet are not licensed, but I wouldn't be
distributing them with the program, and a community around creating new
characters with free software license could be created. Most of the
characters in the Internet use copyrighted sprites anyway, so even if they
were properly licensed they would still have some issues.
Maybe I'm wrong. I'll be glad to hear your opinions. Thanks.