Guest post by "TC" Well, you can't completely blame power rangers for their format...except in the case of the original MMPR. There's usually two females if there's a 5 group (except in MMPR, the original Japanese yellow was a guy named, well, Boy). It's very rare that there's an abundance of female Power Rangers, unless you count the whole thing where they went through, what, two yellows and three pinks in a matter of two years?
Shows based on comic books have no excuse, though.
90s X-men had 4 (Rogue, Storm, Jean and Jubilee--though the kid almost doesn't count), but that has been--to my knowledge--the only time there was a roughly even ratio of male-to-female heroes.