Since the romance and the quests are the brunt of what remains to be done, I have a little clue on what I plan to do.
I'm not planning a large amount of sniping or challenging in the PC-Ano-Surayah triangle. Here are some of the permutations:
Scenario #1: Anomen is romancing the PC. If the PC is a match for Anomen, Surayah will not try to romance Anomen until his RomanceActive is 3. She may sigh a little to the PC at one point, and she will have friendly talks with him, but she won't challenge the PC for his affections.
Scenario #2: Anomen not a match for the PC: If Anomen's in the party when Surayah joins, the PC's going to be out of luck romance-wise where Surayah is concerned, unless Ano goes CN. (And that brings its own problems.) However, if the Surayah gets to know the PC well enough before Anomen joins the party (i.e. enough LT's get to fire), Anomen won't hold as much attraction for her.
In general, Surayah willl see it as her Sunite duty to help the loves of others. She won't balk about Aerie or Jaheira romancing the PC, but rather keep a low profile. She would express a word of caution to the PC in the case of Viconia, only.