Pickpocketing is easy money. Distract the mob, pickpocket them, your energy is back to 100 by then, go to your opener. I just leave the auto-loot option on to speed things up.
To level from 250-300, BRD is your best friend. Solo, you can pick the first 2 doors on the left, exit & reset the instance, rinse, repeat. It eventually tells you that "you have entered too many instances" and won't allow you back in for a bit (not sure how long, I always came back a day later). Within a few days, you'll be at 300. If you are actually running BRD with a group, all those cell doors can be picked as well.