If they want to do another, I think it would be OK to have Mutt as a possible replacement for Indy, but not without strong representation of Indy by Harrison Ford. I would not want something just with Mutt, Indiana Jones is about Indiana Jones, it doesn't get passed on like that. But I'm not apposed to some kind of thing like The Last Crusade with both of them.
Really, I'm interested in some of the other stories, we know that there's a lot of other stuff that happened in between the movies and we really only get the beginning or the end of a section in the movies so I'd like to see those other parts.