halsin's backstory actually has more to do with how the shadorealm formed than with the grove. the grove was what he did after he couldn't figure out how to deal with Ketheric, since he was now immortal. It makes perfect sense being the wandering druid he was before, that he would want to return to that life, and not be stuck at the grove. That's why he immediately jumped at finding a replacement for himself at the first opportunity.
Exactly, he pretty much says he was not really into the archdruid thing and he's happy to have his freedom again.
Other than that I totally agree with the criticism of his character. In my playthrough I actually felt like skipping the grove and focusing on the worm problem but then he started giving Tav all the handy information about the tadpole and the shadowlands and seemed genuinely concerned, useful and invested in what was going on. I found him intriguing initially, I also knew he was hyped during early access so I was curious to see what he was about. After a lengthy inner debate and reading that skipping the grove would make me underleveled and that I would miss out on content, I decided to help him out instead. His story in act 2 was nice, but then everything changed in act 3 when I reached exceptional approval with him. He dropped the knowledgeable, responsible and helpful act and suddenly became a one-track-minded, kinky meme character with zero story, progression and depth. He just wouldn't stop mentioning nature in almost every sentence. Bless Astarion for that savage mockery of him, I was so done with Halsin's nature talk by that point! When he got obducted I was very tempted to just let him be sacrificed. I only didn't because Astarion admitted earlier he was annoying but had his uses so I figured that I could just keep him for the final battle as one of the allies. Next time when I replay the game with mods I'm skipping the grove like I initially wanted to. I'd rather have Minthara in my party than him.
I think Halsin could use a rewrite, just like Wyll did.
