My personal desire for Minthara is not to change how she can be recruited, but to give the evil route a lot more content to make it truly worthwhile, beyond getting a single companion while losing countless others. Going evil locks the player out of so much content, and Minthara does not feel like enough to make it a truly fun gameplay experience.
I've been playing BG1 and BG2 for the first time after getting into BG3, and I really wish BG3 had given as much time and attention to evil playthroughs as those two games. I think moreso BG2, BG1's options are not as fleshed out but it still feels more fun than BG3, for me. There's a reputation system, and if you make too many morally horrible choices it tanks. Good-aligned companions will refuse to work with you/attack you, but there are still plenty of companions who are either evil-aligned or neutral with no moral compunctions. Most quests in BG2 have an evil-aligned way to complete them, that isn't just "kill everyone" and actually changes up the story for that quest and affects how everyone views your character. Your character's storyline is changed quite a bit by going down an evil alignment.
I won't say BG2 is the DEEPEST game out there, and BG1 feels less so, but I still found making the choice to tank my characters rep and play evil fun, not like a loss. I didn't feel locked out of content the way I do in BG3 where you lose way more companions and story beats than you gain. It'd be really great if updates/possible definitive edition gave us more companions than Minthara (Sazza, Nere, the duergar NPCs whose names escape me?) and also added to quests so you have more options than turning them down, or just cutting them super short without much payoff/ending them by killing everyone with little to no fanfare.
(Though, there's also the fact BG1/2 both have a bhaalspawn protagonist by default so the entire narrative is about them uncovering their heritage and resisting it or not. Obviously Dark Urge has that, but then we have Tav and companion origins in BG3...)
