i agree with Nial, nightcrawlers/dubia(any roaches) should be a staple, meaning these are food items that are being given more often, with everything else ( healthy stuff) given in between, we gotta think about costs of feeding too
i feed crickets because my girly loves hunting them, but they have not much of a nutritional value.
actually there's not much to choose from that would balance between cost, availability and nutritional value. say hornworms, they're nice and big and juicy and cost here 1.5-2$ each now multiply it by 15 = 20$ per feeding, and I'm sure after eating 10 worms the frog will still be hungry so it is all about balance and keeping stress levels of an owner under control lol