sonic seemed a bit ridiculous, his recovery is definitely not melee ish at all. his hitstun seems to trap for longer than any melee character ever had, i think hes just a bit too fast and can chain too much lol. god forbid someone was ACTUALLY good with him, they would destroy everyone (no offense thunderhorse, but nobody is gonna have a character mastered at this point lol) i just think his potential there is tooooooo much lol. but i dont know maybe not, it could just be cuz i wasnt sure how his moved works or my DI or something ^^
Keep in mind this is all my thoughts from many builds ago.
Sonic from watching Zeon (who uses him as a third) and actually playing him, I find he is slightly too good not from his move set, but from the current physics in the game. Lack of traction (that is getting tuned up) allows for him to slip and slide around like nuts and do crazy grab combos like no other. When this gets fixed I think you'll see that his combos that look stupidly good will fall apart or be cut in half by good DI (examples being uair and fair chains). His recovery is still pretty tops compared to the rest of the cast but the lack of mobility (not recovery options) balances it out.
I don't quite understand what you mean by meleeish though. His chain combos did not seem any more over the top than a good shiek, falco, marth, etc. I can't remember how the hitstun felt like when dealing with him.
Other than that ridiculous FAir, Sonic's moves don't have that much range and priority. I still theorize that a good Sonic can time the attacks well, though. That's how he was supposed to work, I think.
Priority really hasn't been a problem for sonic for awhile now. Range still gets him when dealing with characters such as Zelda or GW but his ability to duck in or out, pull off a dozen different spin tricks, and now wavedash with a touch of JC grabbing makes up for it.