Re: Humbuckers that are P90 sized?
My first suggestion is that you check those pickups to make certain that they are not stacked-coil P-100s. I can easily understand why anybody would hate P100s.
+1.
After that, P-90 vs HB-sized P-90: not a lot of difference. If you don't like one, you probably won't like the other. P-90 tone/output issues (with any kind of P-90) are often solved by changing magnets. Since there's two, and you can pair up two different kinds, you have a
significant amount of options tonally, far more than with an HB. If you don't like the sound of your P-90's and haven't swapped magents, you're probably going to spend a lot more money than you should buying new ones, and if you do find some you like, it'll probably be the magnet combination that does it.
In bridge P-90's (soap bar, dog ear, and HB-sized) I've used:
A8/A4, A8/A5, A8/A8, A4/A4, and UOA5/UOA5, depending on how much warmth and mids I need.
In neck P-90's:
A5/A4, A5/A5, A5/A3, depending on how bright I want them.
You can also try A2's, roughcasts, ceramics. So many combinations. If you can't find the tones you want by swapping magents in your existing P-90's, then you may not be happy with any P-90's.