I'm a big fan of Wario in Brawl. He played great and is one of my most used characters behind Marth and G&W. There's not much that I would do change him since he's already so great, but his specials could definitely use some work. His A- attacks should use some Wario Land references like the shoulder bash and ground pound, though I personally prefer WarioWare as a series.
Don't get rid of the Bike like in Project M, it's awesome and totally suits Wario. The only specials Sakurai should change are the Corkscrew and possibly the chomp.
The corkscrew was a decent recovery option, but using Wario's jumps+ Bike is more effective most of the time, imo. Also, the corkscrew sucked offensively since it's easy for your opponent to escape and be punish you. I guess it would be a good move if Sakurai either buffed it or replaced it.
Chomp is also a decent move, but it'd be cool if it were at bit quicker. His shoulder bash would also make a good replacement for this move , if it's not one of his A attacks.
I'd also be nice if the Waft charged a little faster, especially since it looks like Little Mac's insta-kill special charges faster than the Waft.
Wario should be a bit taller in Smash 4 since he's supposed be taller than Luigi.
I think these changes would make Wario better competitively and more interesting ton play as. Having references to both WarioWare and Wario Land in his moveset would please fans of both series, which is good because they're both awesome series and there are a lot of fans wanting a Wario Land Wario for Smash 4. (but lets get real, WarioWare is superior and should therefore have more moveset priority
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