Punch line on the drug addict observation is: "I can't get to the gym, he's smoking crack and gets more Likes on his Facebook profile pic change." Or something similar.
Pace less. He doesn't seem to be playing Nervous Guy, but his physicality is Nervous Guy. So, pace a little, then take a stand. Work from the eyes and use the body to punctuate.
Lose the hat and rely less on untucked/black clothing. Screams, "I'm overweight, but I can't face that and hope that you're ignoring it." His jokes are about being odd and out of shape, so let people see the eyes, the face, the bod, and expand the color pallet. Odd is good, if it makes others laugh.
He can do this. He has a good instincts.