The standard path for Minthara is evil (which is a bit odd, as she's no worse than Astarion once you recruit her).
Less evil is the path where you provoke the druids to slaughter the tieflings, then help the goblins kill the druids. It's entirely possible to do that while being a non-evil character - Mol asks you to steal the idol to stop the rite (which might seem like a reasonable option to less-than-wise character), but if you do, the druids slaughter the tieflings. At that point, I think it's entirely reasonable for a non-evil character to throw up their hands and say 'screw it, the goblins can have the lot of you''. You don't even need to participate in the raid in this path, you just tell Minthara where to find the Grove and she handles it herself.
(somewhat oddly, however, your companions all treat you as if you personally murdered a bunch of tiefling children with your bare hands if you do this - Gale's dialogue is particularly out of place for this path).
