There doesn't seem to be from my knowledge. I personally would like the option to make sexual orientation the way it was before. Any Sim can go for any Sim and the only reason for trouble is due to the one your Sim is after is already in a committed relationship. The present system is realistic... far more realistic and complicated than I would like, however. Your Sim hits it off with another Sim, they even have romance in their bar, you think "This could be the one!", your Sim decides to make a move only for the other to say, "I'm flattered, but I don't swing that way." Seriously? Then why were you fine with all the flirting?!