I feel like a lot of the people complaining that the current companions are all jerks either have very limited life experiences where they haven't met a variety of people or have suffered any really difficult or trying times, they haven't played far enough into the game yet, or they've made some bad choices in how they navigate conversations.
For a group of people with their heads on a chopping block, I'd say that they're all remarkably personable. After some time, they even become very warm and I love their playful banter with one another.
This first playthrough has been with Astarion, Gale, and Wyll. (I killed Lae'zel and left Shadowheart to her own devices.)
Astarion has opened up a lot, and although as a vampire spawn he's driven by passion, showing him a touch of respect and occasionally keeping him in check has earned his respect. I let him feed on me when the need arises.
Gale is too caught up in his own situation to really let his walls down, but a little push here and there gets him to be at least slightly warmer. Still very much walled off, but he's letting me peek over the top of that wall.
Wyll has loosened up a lot and has gone from being driven by duty and the desire to purge the worm to relaxing and becoming a bit more playful and nostalgic, and almost downright optimistic.
I'm honestly just a touch jealous that a lot of people seem to lead lives where everything is flowers and sunshine, and so they expect all of the characters in their games to be cookie-cutter jolly adventurers with no shortage of quips, but I'm very pleased by how realistic these characters and their development has been going.