I didn't really take much time to read through the thread, so pardon me if I suggest anything that's already been suggested.
As it stands, SMS Mario (this one) is fantastic, and I'd choose him over the regular mario any day!
Of course, that doesn't mean there's room for constructive criticism, so I'm just gonna post my opinions here.Down Smash
: It's pretty good, though it's really exaggerated. If you take a look at Lucas' Up Smash, that one is far more useful in comparison, though most people still think it's overpowered (it kinda is). With the amount of post-attack lag that this move gives, the insane damage capability sort of makes up for it. I guess you could consider it an all-or-nothing move, a lot like Jiggly's Down-B. Not really my favourite though.Up B
: Absolutely perfect. The maneuverability makes it feel a lot like the hover nozzle from SMS, and gives added recovery at the cost of some damage. I really like this one!Side B
: Pretty good, some people think it's spammy but I think that's fine. As long as you can't combo with it easily, it's fine. It's a really fun move to use and adds to mario's maneuverability, at the cost of having a reflector.Regular B
: It's okay, but mario's regular water gun just seems to be a lot more useful in every way. The only thing I'd suggest really is that you should increase the range OR the knockback by a bit, then it'd be more useful.Down B
: I know you didn't change it, but I had a good idea. You know, his Side B is called the TURBO nozzle, not the ROCKET nozzle. The Rocket nozzle should be his Down B. As for how it would work, I'd say just take Diddy's Up B and rework it to have water effects, and a bit less horizontal capability, if you can. That'd feel just like the old rocket nozzle from SMS.Down Aeria
l: The ground pound is pretty good, but in every game mario's had so far, it's a stall-then-fall attack. It looks perfect and functions perfect, just make him freeze in the air the moment before he drops.
And that's pretty much all I have to say. I hope you found my advice helpful, because I'm not trying to sound like a [censored] here.