Black soldier fly larvae (under the brand names of "Reptiworms," "Phoenix Worms," and a few others) can be used as staples. Of course, there are always differences in nutritional values, no matter what you feed as a staple, so it's always good to try to provide some sort of variety. Another thing to note about black soldier fly larvae is that they have a fairly ideal ratio of calcium and phosphorous (unlike crickets), and therefore do not require additional calcium dusting.
But if it's a financial issue, I do believe crickets are a lot less expensive IF you order them online. If you're buying crickets from pet stores, they are very pricey. For instance, I used to buy about 500 crickets a week for $50 at pet stores. With $50, I could've bought about 5000 crickets online. Whereas buying Reptiworms, I can get about 1500 for $40. So honestly, if it's a financial issue (and not a personal issue), and if you have the choice to order between the two, crickets are definitely cheaper.
From my own personal standpoint, I switched from crickets to Reptiworms because I can't stand crickets. Probably the only kind of insect I am actually afraid of. I'm not even scared of spiders or wasps. Crickets just give me the heeby-jeebies.
The feeding schedule looks great by the way. Somewhat of a side note, however: all bearded dragons DO grow at different rates. Take a look here, and you'll see a lot of different dragons with different ages and lengths:
http://www.beautifuldragons.503xtreme.com/Growth.html. But I do have to say that his length and the picture you provided makes me think he must be at a juvenile age, if not younger. Plus, the fact that he's eating that many crickets daily makes me think he's most likely younger, as adult bearded dragons don't need protein daily and certainly not in such great amounts. But to be honest, it doesn't quite matter how old he is, so long as he's eating and being fed properly and growing up healthy. Most "adult behaviors" seem to be linked to size rather than age, anyway.