Well well well! i was looking at this thread just some days ago waiting more fans and i found an awesome discussion about the whole alignement system etc etc!
I really enjoy all of you discussing about it and i try to make my own opinion about it since well, i never took my time thinking about alignement system because i always played all the pc games of D&d and never at the tabletop.
So for me evil is doing evil things and good is preventing evil doing the evil things and sometimes helping others and so on.
I am an huge fan of the Drow Romance in the previous game and the whole "redeem arc" was optional just so you know, i replayed specifically Bg2 multiple times and romanced Viconia and my favourite romance option was to play an evil character and don't redeem her (also because to me redeem Viconia make her lose the part i love about Viconia, bein a ruthless, strong leading woman and independent. So it give me the impression to broke her making the whole redeem).
I hope the same here with Minthara but butchering a whole village isn't starting material for a redemption arc, its sound like a one ticket straight to hell with Minthara!
I mean if you are roleplaying character in no possible way you could side with Minthara ever! So that's lead you to being an evil character and here the problem, why a selfish character should help those cult of tadpole controlled if there isn't a real personal gain?? Larian should give the evil player more reasons to join Minthara.