Been answering that when I was on my phone, so I wasn't too keen on writing long.
Personally I think that only a cloud of fetishes would be somewhat contraproductive and I'd see it as a step back. Rarely do I look for a single fetish only. Plus, with E's nature, searching for a certain fetish can give you results of very different players with very different tastes. If you're interested in heterosexual RPs in general, searching for "collars" can bring forth both those who like to give and receive as well as all genders and orientations.
It would simplify the search, yes, but it would make targeting the right person all that much harder to find. In my opinion.