If Minsc is a spellcasting Ranger, he's out. If he's a Barbarian like he should, I will give him a chance. IF they can explain convincingly why he's not level 15+. Same with Jaheira. I hope they don't mess up these legendary characters.

Minthara is only good for "look how evil I am" talk. The way she was groveling before Ketheric Thorm, not impressed. She's a Paladin but where's the conviction? She's out.

Astarion is out by default because the whole vampire schtick feels like such an afterthought and forced. Also not explained how an undead creature can get tadpoled in the first place. Entire vampire theme wasted by some blind desire to include a vampire companion too hard and too early and not do it properly.

Halsin is unfortunately out. He should have been a high level NPC as First Druid. The leader leaving his Grove when his Druids need him the most, because players grasped on to the first good aligned hot guy in EA and harped on him becoming a companion, is not believable or a good look for the character. Halsin's purpose as a character was to be a level 9+ NPC that would have shown the player there is a power structure in the world. That the low level party is not the shit. Halsin is the shit. But also a promise you can become that powerful later. He could have swooped in to save the party's ass at the darkest hour, by taking on a boss too powerful for the party and potentially sacrificed himself in the process. But such strong scenes are secondary to players' romance cravings over at Larian. Could have also given them the romance while keeping Halsin as an NPC.

Wyll is out unless the rewrite is substantial and successful. He was such an oddball being one of the lads, like serving a devil from the Nine Hells didn't change a person at all. It was more like Mizora was his boss at McDonalds you complain about. Needed much more significance to devils and warlocks there.

Gale is ok, just his backstory is so over the top I'd rather not have heard it at all. Karlach the same. Less would have been much more with these characters. But I need someone in the party.

Shadowheart will make it. But hopefully she has a redemption arc sooner rather than later for good and neutral parties. She has the potential to be the most interesting and cool out of everyone. I hope her real name isn't Karen.