I just think it's disrepectful to the individual series when crossover games do a poor job to represent specific games and characters. I know things wouldn't be as fun if they worked perfectly, but franchises don't want their creations to be misinterpritted and confuse players. Little additions and tweaks to things like attacks and such aren't going to offend anyone, but changes in personality and specifically defined character abilities are unacceptable.
I think continuity in SSB has the most difficulties when you bring Zelda characters into the mix because they aren't constant between games. I know SSB can't revamp their characters completely just to accomodate a new game, but simple things like replacing a move, changing the appearance or adding a new effect aren't just within their grasp (because they've obviously already incorporated them), but it's also something I'm sure the specific game franchises appreciate.
I think continuity in SSB has the most difficulties when you bring Zelda characters into the mix because they aren't constant between games. I know SSB can't revamp their characters completely just to accomodate a new game, but simple things like replacing a move, changing the appearance or adding a new effect aren't just within their grasp (because they've obviously already incorporated them), but it's also something I'm sure the specific game franchises appreciate.