Use your creature or summons to take the heat.
As soon as you see them fire their bows, use the flying barrel roll to avoid them ,then attack. Their ranged attacks have a cool down timer.
Raise your vitality so you can take a hit.
Use cover..
I use my creature alot..sometimes I just let it fight while I watch. It has 2x the HPs I do, way higher melee and ranged protection and is almost immune to magic.Plus it can cast wicked spells.
If this were a FPS..my creature would be a perfect meat shield.
And there is nothing wrong in running away...ahem..I meant Tactical Retreat.
Charm is one of greatest battle turners..it's the only magic spell I use.
Just run in and charm someone and run away...repeat if necessary. Thin the room out in no time.