How old are the dragons?
The hornworms will grow very quickly. At full size, my 1 year old will only eat two at a time. The BSFL will also grow quicker than the rest, so I might feed those off first and supplement with your roach colony so you don't have to worry about running out of roaches but your dragon will also get the protein boost. About the free-feeding, the roaches can climb silicone inside tanks if you have the dragons in aquariums, so I recommend only feeding one roach at a time or in a bowl until they are finished and remove them so they don't escape. And you may not want to free-feed crickets as they can bite on your animal and generally just bug the crud out of them. I don't use crickets, only in small batches and as treats, because they stink, escape, and die so quickly, but we all have our preferences.
Also, if your dragons are adults, the BSFL will be too small. You'll need to grow them larger as many dragons will just swallow mouthfuls of the small worms and then poop them out alive, not gaining any nutrition. You want the worms big enough to force the dragon to chew. An adult dragon can eat 100+ worms in one sitting, so they may not be very economical.