I remember back in TS3 someone requested this for CAS and I and many other people gay or straight all agreed we didn't want labels because we didn't like labels in real life. However, I eventually changed my mind. This would be great for many types of players. Because some were afraid if this was set in stone in CAS then their Sim couldn't change their preferences. However, Maxis has been very good in the past games of creating code and not so rude interactions of Sims to refuse a flirt with just putting up a hand to say no, I'm not interested if the other Sim was not their type or their chosen attraction gender. They could do that now, if they added sexual preference to the game. The Sim could just politely say, I'm not interested. It's been in the game since TS1. Why it's not in TS4, is beyond me, or I have never seen it.
Edited to Add:
They could add a text to the player 'Do you want so and so to accept the flirt?' if it came from a Sim who is not their preference and the player still be in control to answer yes, change their Sim preferences or yes accept it.
