F3 needs to be a mid, because he already has no mixups at all.
Define 'mixup'. If to you a mixup is being able to mix low and overhead, keep in mind that strike/throw mixups are also a thing and Johnny is a master at it due to standing 1, standing 2 and F3 staggers.
The problem with f4 is that it is too fucking slow and too negative on block to the point that it is useless to throw it in mixups.
Which is why people tend to use it as a whiff punisher, to catch people ducking or to force a reaction after hitting amplified forceballs.
You are at only fucking +3 WITH NO GOOD MID to keep the pressure going.
I heavily disagree. While F4 is a 14-frame mid giving an 11-frame gap, there is still plenty to work with. Let's say your opponent expects a F4 right after you do amplified forceballs and they poke back with whatever string or normal. You can:
- Slightly delay F4 to whiff punish their attempt to hit the earlier F4 they expected you to do.
- Go for a jump-in.
- Whiff punish with B34 instead.
- Dash up throw if they always respect F4
- Dash up D1 if they expect dash up throw.
etc.
Hit your nutpunch? Congrats! You are only at fucking +5, with once again, no good mid to go for a blockstring.
Which is why you have an actual mixup between D1/D4 and throw after hitting a nut punch. If you hit a D4, you can jail a F3 into a stagger, F344, etc. If you hit the throw then neat you get 14% and you're in good zoning range. Also, if they try to duck the throw, you can make a read and B34/F4 them into a full combo.
Give Johnny's F3 mid properties and I assure you he's not going to be in autopilot nor a top tier character.
Why would I use any other string besides F3 though considering it has amazing range, leads to an insanely easy hit confirm and F344 gives just enough pushback to give you some space in footsies?
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Making F3 a mid would be a solution to a problem Johnny does not have. I think you underrate F4 and Johnny's mixups (not low/overhead but strike/throw/stagger).
Are you on PC by any chance? I'd love to fight your Johnny if you do, see how you play him.