I'm in the middle of Act 2 and here's my opinion of all the companions so far.
Lae'zel: I didn't like her at all first, but then she told me she loved how I stink and I realized she's just an angry little guy. She's so pissed at all times and I like how she hisses at me. Girl you are fucked up. 10/10, will romance her at some point.
Shadowheart: Ngl she was a little bland but very easy to get approval with so she was my bestie early on. Now that she's revealed her religious trauma I think she's a poor little meow meow. She should be a tumblr sexyman. 10/10, will romance her at some point.
Astarion: Went in hating his ass thinking he was overhyped. Got brainwashed quickly by the horny voice and the laugh lines. Hated him again when he kept being a little bitch. Hugged him oh so tenderly. He likes it when I tell people to kill themselves. 10/10, will romance him again.
Gale: Was considering romancing him until the ex reveal. Big turnoff for insecure bitches (me). Act 2 started and I got interested again because of the angst. He's funny and his dialogue is the best written/wittiest out of all the companions. Accidentally led him on. 10/10, will romance him at some point.
Wyll: Thought he was a bit bland at first ngl. Very standard backstory. Probably the best-looking companion out of all of them. Got extremely easy approval with him despite not bringing him around often. Then I realized he's charmingly silly but deeply genuine with his heroic aspirations. 10/10, wyll romance him at some point.
Karlach: Best girl, no contest. Loved her from the start. Big, fun, funny, good heart, and boy she can do a LOT of damage on the battlefield. Absolutely waifu material. Touchstarved and gorgeous? I'm straight but she could get it type shit. I want her to split me in half with a single pelvic thrust. 10/10, will romance her at some point.
Halsin: Liked him from the start. He's fucking massive. My Tav looked at him with lovesick puppy eyes in every early custcene so I was considering romancing him in the beginning, but he's way too nice for them lmao. No notes, he's literally just a giant teddy bear of a man and I love him. 10/10, will romance him at some point.
All in all it's pretty impressive how Larian got jackpot on all of these little freaks. I can't say I dislike any of them.