I feel like it comes down to each individual, but if you're looking for my two cents:
I find bestiality repugnant on basically every level.
Again, with ageplay (assuming underage means "under eighteen" but still within site rules), there was a time in my life that I found it more acceptable than I do now. As I've gotten older, or perhaps as my tastes have matured, I find myself keeping ages within the general vicinity of my own. It's a comfort thing, and not indicative of what women may, or may not, want.
As for Non-con, I'm not entirely opposed to it, but that's heavily dependent on my mood, or what I'm looking to get out of a story.