Toon Link is not best or anything, but people underestimate him. He is maybe lower mid, which is still amazing in PM. He might have some stage counterpick issues, as well as issues against really good edgeguarders similar to problems Falcon and Ganon have there. Because, you can bomb jump and such, but if they keep hitting you back offstage... One weakness could also be ranged pressure where you can't do upB OoS or nair OoS because of the range but the grab is too slow.
All of those are weaknesses you can clearly work around, and Toon Links neutral game is at least average, which is, together with his good mobility and his projectiles, a sign of a good character. He is definitely legit.