I've been wanting this since the Sims 1. The option to choose your Sims' sexual orientation (gay, bi, straight.) That way when you befriend someone you don't get wants to kiss/etc with one of your ...
Well, my reasoning for this was because it seems (at least in my experiences) that Sims by default are bi. So I find it irritating when I'm playing another household and I see my other original Sims flirting with someone of the same sex and beginning a relationship when my plans were for them to be straight. Or my gay/lesbian Sims flirting with those of the opposite sex when I'm not playing them...that's especially irritating.