I think the way to handle Halsin is to have more actual Druid stuff for him to do. Act 1 and the first leg of Act II is where we spend the most time in the wilderness, so it's weird that our Druids don't hop on board until basically Act III when we're in the urban environment and where things feel decidedly less Druid-y. It works much better for Jaheira because she has the Harper angle and the home town advantage.
If Halsin dies in the Shadownlands it feels so anticlimactic given everything that goes down and how much time it takes just to even get to that point. Wouldn't it be more interesting if he came back as Dark Halsin or whatever? Maybe that works, I don't know, I mean the entire shadowlands set up frames it pretty well. Then we could have a Shadowdruid and Halsin would instantly become way more interesting to me.
He even says at one point how "maybe Kagha was right." Failing to lift the curse on the Shadowlands might have ramifications beyond just "hmmm guess he's dead now? bummer."
He's built up at the Grove into this larger than life figure and he talks a big game, but get out in the field and it's frustrating that he just basically hibernates for the whole section of the campaign where we'd probably want to have a Druid in the mix.
If that's too boring, bring back some version of the helm of opposite alignment from BG1 and tie it an item? Or leaving that idea aside, maybe try something totally different, but also recalling BG2 (though updated for a more present day sensibility...)
Halsin might also become some sort of Tiresias type figure, if they included something that recalls the Girdle from BG1, the one that you could nab off that first ogre on the way to the friendly arm inn, but presented with a bit more tact. They do that already with the Guardian, but they could give Halsin that angle maybe to make them more interesting. They had nocturne, but kinda hidden in Shadowheart's quest. Games tend to suck at the two spirit thing, but basically bringing Kagha and Halsin into a single character, and folding that into the shadow druid sub plot would be pretty on theme for the Druidic lore.
Basically Chauntea and Silvanus in the same character, with the shape change keying off things like player inputs? That would satisfy some of the romance issues maybe or stuff mentioned elsewhere, but just making him into like pure projection, whatever the PC is after. Halsin could basically take over from the dream guardian, but as a shapechanger. Perhaps with changing attitudes on all sorts of stuff, keying off what the player wants most, conveyed to the game through dialogue options. I don't know why he should be the most controversial, or any more or less controversial than any other character, but if that's the case, then one potential blueprint might be to make the Arch Druid of the Emerald Grove into like the main romance of the game, if one elects to explore it. They got all that stuff with the Zethino at the circus, that could play into the set up for it, also since we have Lucretius there too to kinda seal the deal. It would be a cool metaphor about what constitutes nature too. Letting it just be normal and natural without making that stuff all charged. Perhaps Halsin is not the right character for this, but I imagine they could do something that isn't the point of it, but just one of a series of potential and equally viable options.
Effectively taking the papa bear trope and transforming it into something a bit more meaningful. Like some kind of lesson about know what you want. If Halsin is the game's libido, maybe broaden that concept so that the player can get out of it whatever they want to put into it, comfortable in their own hide as it were.
I think they should do something to differentiate him from Jaheira in the party comp too. Having 2 Half-Elf/Elf druids that are so similar is kinda strange.
We know Jaheira got to experience true love with Khalid, or maybe Charname depending on one's memories of BG2. BG3 did a pretty good job of making up for Anomen in BG2. Pretty much all the romantic tropes are already covered, except for the one they teased with Daisy and the Dream Guardian, but maybe Halsin could work an angle more like that? Since we lose the dream guardian at that point, but maybe the Arch Druid could maybe indulge a similar fantasy. Sorta like I can be whatever you want me to be, and then just let the player run with that wherever it goes.
The fact that Halsin doesn't have a tadpole would make it more meaningful, since he can't read our minds. That's why the player has to tell the game what they want via the dialogue. Maybe Elf with guns was just a form he adopted at some point that suited the dynamic at the grove, but he could just as easily become a Dwarf or Dragonborn, and Adonis or a Moon Nymph, whatever sort of stuff the player vibes on. Maybe that mask we get in the chest at the very start of the game has additional uses. Instead of the Bear that did the hype shock stuff before release, he could become something more abstract like this...
https://en.wikipedia.org/wiki/Erotes&
https://en.wikipedia.org/wiki/Peitho&
https://en.wikipedia.org/wiki/TiresiasThe last fits particularly well, because there is already a nekyia interlude in the shadowlands with the portal business.
Somehow I doubt we get anything quite so elaborate, but basically using this character for the same sort anima/animus projection thing that happens during character creation, except here instead of using it as a foil, it could just be a nice side piece that lives in the game without necessitating main plot support to justify its existence. I think it could be adaptive, since they could do stuff with voice as well. Canon appearance/attitude would be the default, but then it could just riff from there to teach us whatever we want to know regarding the birds and the bees. Romancing the stone but instead of Pygmalion it's done up more realm's style. Like Maybe with some stuff about Elminster, since he's an analog in this setting? Not sure, I but nature could probably find a way to make it compelling.
The central idea being that our character, who is meant to represent nature in the abstract, just kinda affirms what we're about on that score, like maybe from a dozen thematic options, and makes it all normal so we know the oak father and magna mater are chill. Rather than roulette or gamifying stuff overmuch into a challenge or puzzle, it just becomes an allegory for being chill and accepting. I honestly don't know how to pull it off with tact. But I feel like if you somehow put the performers who acted out the Dream Guardians and the performers who did Halsin and Kagha in a room together with this in mind, they might be able to come up with something better than I could just rambling off the cuff, but at least it's an idea. I type too much probably, but just seemed like a cool angle. I'm also way more forgiving off idiosyncrasies in the main plot, when at least the characters are expressing something beautiful or wise or clever in the margins. Like it kinda makes up for other stuff when they hit stride there, so maybe that could work.
Or just a more prosaic option where we get some romance-agnostic Arch Druid stuff too, the same way a few other characters get their follow up quests in Act III regardless of whether you're partnered up. But even if we don't get any of that, and nothing changes, which is also perhaps pretty likely, just to get Halsin in the party sooner. That'd be a win I think
