Not exactly; I think he's viable for tournament play and definitely has a chance against top chars (rosalina, sheik and diddy) but he struggles against some other chars.Might wanna rethink that Shiek matchup. If MK can at least go even with the top 2 characters of the game (Shiek, Rosaluma), hes easily in the top 10.
I think he gets his best from having at least a secondary character. You take care of lower tier/bad matchups with that char and go mk for everything else