Previous playthrough, I went through most of the game with Alistair, Morrigan and Wynne. This playthrough, that's still the core group, though I sometimes switch out Morrigan for Leliana, and occasionally take along other characters just to hear their banter.
As I said, I'm romancing Leliana this time. I turned Zevran down early, but I think Alistair might be trying to start something - his approval level is at Care for some reason, even though I haven't been very romantic with him. But that's not going anywhere for various reasons, one of them being my character already has a girlfriend
Also, I wish this forum had spoiler tags so we could discuss some of the endgame stuff...