People disliked Other M for the WRONG reason, I can say that much (the gameplay was wack).
But nah, Nintendo never really expands on characters, they focus on gameplay, which is much better than trying to have a good story and failing miserably (like 95% of the games that have come out in the last 8 years!) Probably better to keep it that way. I dunno what they were thinking getting Team Ninja, who DOES make some really good games, don't get me wrong-- to develop Other M when they could have done so themselves.