Mika doesn't need nerfs.
Ryu, Chun definitely need nerfs.
Ken probably needs nerfs
Laura, Gief, FANG, Juri, Ibuki definitely need buffs.
Vega claw-on normals need buffs
I disagree that Mika doesn't need nerfs, although in her case, her strength comes from how she completely upends the gameplay style they've gone with for SFV, so she's probably the most complicated character to balance and that can be approached in different ways.
Flatout, I think the only across the board nerf no matter what that she needs is the hitbox on the clap. That shit does not need to be what it is. It's too big of a reward (corner carry from anywhere on screen with one bar of EX, with the things SHE can do in the corner? Get out of here Capcom) for how braindead it is to throw out in footsies. You can probably make it come out slower instead of a hitbox change if you want, so you can still use it smartly to whiff punish instead of just mashing it right outside of opponent normal range without thinking.
Now, in general what makes her so strong is that she has the absolute craziest resets in the game outside of Urien Aegis shenanigans (but hell, he needs fucking V Trigger to do that, Mika gets it for free, on top of getting even more options with Nadeshiko) and since the game inherently rewards such aggressive playstyles; her numerous options in the corner, high damage, high stun, 3 frame jab, +1 on block crush counter, and not the worst reversal option in the game make her far too strong.
I get the conceit of her character is to drive you into the corner and make you guess to high hell, but my argument is that it is far too easy for her to get you there, and once she does, she has so many options, that she is allowed to make too many safe guesses that high risk gambles aren't necessary, which should be the complete opposite of how her character should be played compared to how quickly she can end a match.
