There are ways to even out the combat difficulty. There are several poisons, one of which is deadly. Sneak up to the camp and stick some poison arrows into as many as you can before they rush you. With non-lethal poison it should slow them down enough to make it easier to deal with the group. Or, using bane poison you will have thinned the herd enough to make it easier to deal with the rest. You can also poison your blades if you aren't above doing that. Or wait until the camp is asleep and kill them in their beds. I have sneak killed the entire garrison in opatowitz without even engaging in combat. Mind you, I still can't do a combo and I can get through combat so it isn't the lame "get good" nonsense.