EX peach is a good reversal punish for negative stuff that people like to throw out that they think is safe. Like a very well spaced balrog mp dash punch. -6 and hard to punish when well spaced but mika can get a punish for free into some good corner carry with ex peach. Same goes for well spaced over heads like Urien's.
And buttons? Her go to shit like slide and cr hp are noob traps, I think. The buttons that mess me up when fighting her are st mk and st hp. Those shits are hard as fuck to whiff punish.
I don't know lol. I don't really play mika, just remembering how nando got in my business with her.
I could see that a bit for that kind of long-range negative poke, but the recovery on EX Peach means that it has to be telegraphed if a Mika wants to punish with that. A bunch of characters have ways to deal with those situations that also gives corner carry. I wouldn't call it amazing by any means, but it's decent for that purpose.
cr.HK is an bad button. Very situational, but decent if a Mika knows when to use them. cr.HP is now also a bad button. A Mika who uses it will be negative in the opponent's face. If you watch top level Mikas now, they're not throwing it out unless they have a V-Trigger cancel on deck.
st.MK is good. Doesn't convert into anything, and is fairly slow, but it has decent range. cr.MK is better than that. st.HP is also good, especially with the damage buff, but it's not a particularly notable button.
She's got tools that I could describe as "amazing" (notably, corner stuff), but neither her buttons or her EX Peach would be one of them. Lady Mika's her best button, and the only one that could be described as "amazing." Even then, it even falls short compared to ones like Rashid's cr.HP, Urien's st.HP or Balrog's st.HK.