From what I've been reading since Fleshstick got nerfed is Bar room brawl might be the best be your best ticket. You may want to double check your sidequests and see if there any that to do for XP only or that have Eridum rewards. Maybe some of your green rewards also.
Assuming killing a raid boss gives tons of exp, and you don't mind evil smashing, i'd say evil smash an infinity and repeatedly kill Hyperious. But I could be wrong about the earning exp for killing him I'm always lvl 50 when I attempt a kill. --- And I'm all out of bubblegum
Tier 3 Bar Brawl is the best way to level up your character. Hyperius only give you a thousand xp per kill, then after every ten to 15 time you have to kill his robots and pick up his stuff. Good for farming, but bad for xp.
Use a norfleet, either explosive or caustic in the Tier 3 Bar Fight. You can stand by the entrance to the bar and kill everything without going into the bar. In True Vault Hunter Mode you should be able to earn about 20 to 25 thousand xp per challenge.