Well obviously using sex appeal to garner interest/heat or anything of that nature is effortless, easy, and most importantly effective. Their is no point in trying to dispute that fact.
However, I will come to the aid to women's wrestling. I honestly think that women's wrestling could be a viable draw and that you don't necessarily need to focus them around sex appeal for them to do anything positive for your business. For starters, you can point to all the rating losses or anything to that extent with WWE for the diva's division in the past few years but honestly the only difference between the diva's division and the male division (Okay, I know the division's are a little more separate than that, just go with it) isn't the gender. Ever since I began watching WWE has had the same method to booking the diva's, crappy and in under ten minutes a week. WWE hardly ever attempts to construct anything but the most basic storylines for the divas, without really developing anything but the most basic characters (like for today, how many diva's actually have discernible characters, pretty much all heels and faces are exactly the same [yes, this can extend past this division but that's where the next part comes in]), and finally with very little time devoted to them. You think John Cena would've gotten over like he did and as big of seller like he did if they only gave him six minutes each week and with barely any mic time or real angle? Oh, and based on what I understand, they're reprimanded when they wrestle too good. Michelle McCool brought up that her and Melina were yelled at for their match of Night Of Champions 09 bout being two good and that can't be seen as good as the male wrestlers, to make them better you know that thinking, and then Jericho came over and asked him would he please shut the hell up. Granted that could no longer be the case or just an isolated incident but I felt like bringing it up. It's a fun story.
Now, I was planning on researching the ratings segment by segment of the few angles I can think of that WWE actually put some effort into or some segments WWE gave a chance to but um, those angles happened like seven years ago and I couldn't find anything. However I'll bring up what I can and speculate. Back in 2004, Lita vs. Trish Stratus for the Women's Championship was the main event of Monday Night Raw. I thought it was a great match but what's important here is that WWE actually gave a diva's/women's match the main event and gave it some pretty good time. I don't actually know how the segment translated into viewership but I imagine it had to be doing good prior for WWE to actually book that. And that Trish/Mickie feud went over really well from what I understand. And I know, their was lesbian overtones, and actually lesbian moments, god bless 'em, but the focus was still mainly on the championship. It was still building towards a wrestling match, and from what I know, it worked well. You see, they can still use sex appeal, it doesn't have to go away but you can just use it to further investment in the characters in the division, and try and slide it into match development. It is possible to garner interest without it, you just have to treat it like you would any other segment, you have to develop characters people can be attached to and develop feuds that can garner interest. TNA did that well, hell I remember reading a bunch of reports that TNA's second show was going to be an entire show based around the Knockouts. Though that never happened of course.
And just like that never happened, I highly doubt WWE will ever figure out how to properly build a diva's division so that sex appeal isn't the only going for it. Because WWE doesn't know how to apparently, they've spent so much time booking that division purely around sex appeal that without that crutch that don't really have a concept of have to promote it. And even if they did, with all the years they've spent having it be nothing, the effort required to make this worth is too much for WWE to spend time investing in. It's not an easy thing to do, especially when people are so use to the precedent set that it's not worth it. But my point is, that with a smart booker, who actually doesn't mind putting in the effort, you could market that to be a success. And while it shouldn't be the focus or the only reason we care, there is nothing wrong with using sex appeal to help get that going or just as part of a feud now and again. Obviously I don't have anything against sex appeal, my avatar is of my Stephanie McMahon's ass after all.