Only speaking to what I know: Irvine's not the middle for English - on pretty much every (admittedly unreliable) rankings system I've embarrassedly glanced at, in the order of UCs in English it's second only to Berkeley and LA. I've heard Santa Barbara spoken of well for English also, and Davis was rumored to be on the rise. For crit theory, certainly, Irvine is pretty much tops. I'm more familiar with their faculty in early periods, but I had eclectic tastes and all the American lit people I know there are really amazing. There seemed to be plenty of interest in gender studies - I don't know if this holds with the budget issues, but they used to fly Spivak out from New York every spring to do a grad seminar.
So for the UCs you can't look at just their general reputation, you have to be very specific, not only regarding department but also regarding your particular focus. Not only that, but in certain schools related departments work together more amicably than in others. UCSD has English and Comp Lit combined, for instance, and Santa Cruz has an atypical structure generally. Also, sometimes programs have different names: Irvine has a special crit theory grad emphasis, while Berkeley has Rhetoric. Different, yeah, but in many ways they're comparable, or at least may be attractive to similar applicants. Then you also have to consider regional issues. LA, Riverside, and Irvine people seemed to get together a lot. Professors go to conferences or even guest lectures at the other schools on a very regular basis, and grad students consult faculty at other UCs - so there can be some community between the campuses, especially those in the same region.
My best advice: approach the different UCs as you would the different schools of New Jersey: you wouldn't lump Princeton and Rutgers in a bundle - they're both good schools for different reasons. Indeed, ask your advisors to point you in the right direction, then look at faculty bios.