With how balanced the rest of the cast is, the stand-outishness of the 'strongest character', regardless of who it may be, is questionable.
There can be a character easy to play or low risk/high reward, but that character shouldn't dominate the entire cast. That's ludicrous. There needs to be at least a few hard counters to every character, so that in the event where someone smug thinks they can win a tournament set by switching to Diddy, someone else can switch to the hard counter, instead of the same character. Or hell, MAIN that hard counter so nobody who fights you can switch to Diddy for a free win.
Regardless of if a character is statisticly better or not, stand-outishness should be snuffed by pulling out a character nobody expects and winning as a result. That hasn't happened yet, and it's questionable if it will. Is that a result of a bad character, or bad players?