Being a monster doesn't mean other monsters won't attack.
I think they need two or three torches to offset Karla's "bright" character.
You should probably have more than one torch, though.
Sure, "Calming" Spell. Might get her a level 2 Calming spell if you give her some chloroform.
Not sure if spiders sleep.
It doesn't count as a casualty if it's in the plan.
She's not wrong. Her actions can certainly strike the hearts of monsters. Just give her a sharp enough blade.
This is basically three-quarters of the D&D groups I've been in over the years.
And who are you? The useless Fighter, the Evil Cleric, or the scared Wizard/Sorcerer?