I have read on several dog forums I'm a member of, that some dogs don't do well on Blue Buffalo (diarrhea, some vomiting, don't like the life bits, that contain the vitamins/minerals). I'd look for a kibble that's low fat to avoid another pancreatic incident. Some people have had good luck with Natural Balance LID diets (simple ingredients and low fat %). You can find them at Petco and other pet stores. There are other good choices too, but you probably should stay on the vet diet until he's stablized.
This type of dog should never have table scraps, b/c they tend to be too high in sodium, fat, and sugar for dogs. I have dogs with normal stomachs, and I don't give them table scraps, just on principle. Exceptions are unsalted canned/frozen green beans, baby carrots, and very small pieces of fruit (apples, watermelon, bananas) on occasion.
I hope your dog feels better soon!