The only other thing I can think of as a comparison factor is body hair. If you naturally have little amounts of hair on your arms, slow-growing or thin leg/underarm/crotch hair, and eyebrows that do not need plucking, I am jealous of you. But that's by far not a universal (or really that important) factor. I would say that ladies have risen above the need to compare but I feel like that probably isn't true. It's just a different kind of category, like moms bragging about their kids or hot hubbys or whatever instead of something immediately attached like their genitals.
I think something essential is lost in the comparison. Having more body hair doesn't necessarily make you less of a 'woman' ... It doesn't mean you can't please a guy. I think women compare CONSTANTLY but not in the same way. I don't think guys actually physically compare much either, except metaphorically.
The only remotely equal insult I can think of for a woman is saying her vagina is a gaping hole, or some other way to say she's not *ahem* tight enough to please a guy. But that isn't really a rampant self esteem issue.... (This is an assumption, it could be totally off)
Tough to talk about this without being bashful
Also, on the breast size issue: Some women just have to come to terms with their self image and realize their breasts are beautiful even if they do attract pedophiles instead of frat boys.