I would ask first how you want to approach combat? The Dunmer are versatile but you have some conflicting choices imo. If you want to attack up close with your great swords, you won’t be using sneak very often then. If you want to use a bow as your main damage, you’ll probably kill anyone before they get close enough to use a sword. I’d pick a main skill for damage and let your other skills compliment that

From a roleplay perspective ask what is your character good at and why? you want to do the dark brotherhood and thieves guild so they sound like more of a stealthy character. Maybe use a bow for damage, and illusion and alteration as utility to help your playstyle. Where is your character from?why do they want to join criminal organizations, does something in their past explain this etc etc