The best diet would be mostly earthworms and crickets/roaches. Superworms and mealworms aren't very nutritional. Mice are a little too rich and very fatty. Many people have had problems feeding too many rodents.
The large night crawlers Walmart sells are the Canadian night crawlers. These are very difficult to breed in a captive situation. But I hear European and African night crawlers are much easier to breed. Africans are supposed to be the fastest breeders. I use lobster roaches for my frog but dubia were mine(and his) favorite.