Well the numbers would argue it. Three on Voyager, two on TNG, two on DS9, two on ENT, one on TOS. Jadzia/Ezri and Seven/Kes cancel each other out since they basically replaced each other.
As for which cast was better? Well you're going to have as many opinions on that as posts. Really Trek did their females a disservice on many levels by either just making them into two dimensional characters or self-parodies.
Uhura really was just a glorified extra. Troi's just hard to take serious. Crusher's there... probably doing something important, but not too interesting. Kira was a nice change with a strong female, but even so her anger made her a parody sometimes. Jadzia was just too random. Drinking with Quark one episode, aloof scientist the next, killing people with Worf the one after that. I found Ezri refreshing with a nice set of flaws and strengths that seemed real, but... she really was just an afterthought. Janeway... let's just say I'd take her strong character more seriously if she didn't contradict her self so much. Torres was really... stereotypical Klingon. She either fixed things or smashed them. Kes.. really had no plan or designated purpose beyond she was there, had mysterious powers and... yeah. Seven was an awesome character... but was objectified in that catsuit to the point where you just wondered how seriously they took her? Hoshi... seemed a realistic character but faded to glorified extra. T'Pol... also objectified but she makes up for it by being bitchy at every opportunity.
So who had the best female cast out of all that? Well I can say I think DS9 had the least worst female cast anyways...