I see soooo many people morbidly obese and shooting at ranges. Why? It is unhealthy. Did the spoon or fork MAKE you fat? NO! If you need to run and duck for cover when you are overweight, are not you going to think that you need to be in a little better shape? Also when you actually do run and duck for cover, will not your heart rate be at a better pace so you can shoot accurately instead of panting for breath while trying to hold a gun steady?
On the other hand enough fat might stop, slow or deflect a bullet. Or the added mass might make someone miss the vitals- kinda like a mongoose does when he puffs up in front of a snake. I just gotta figure a way to get that up on my chest instead of around my belly.
Anyway, some very good suggestions here. Another one I caught from a Jerry Barnhardt tape is to strengthen or speed your draw. Just take a 12# dumbell and work your presentation with it.