So I've been Soloing Black Talon trying to get Vette's affection at a decent level. With only one "Disapproves" option (killing the Captain), I can get just over 6000 affection per run if I pick the right dialog choices.

 

My question is this: are there any higher-level flashpoints that can help me get a decent amount of affection for my other companions? I feel it would be much more effective repeating flashpoints than doing it through companion gifts.

Wow. That's a lot of points. Unfortunately while I've not done them with the goal of raising companion influence in mind, black talon (and the esseles, the pub version I believe) have by far the most dialogue in them so you are unlikely to get as much bang for your buck elsewhere.