1) I just got his adult tank now. Yes, my frog only uses about 5 square inches of this tank. lol. I find the main problem with a big tank is live feeding. Too much space means that the prey rarely goes in front of the frog's danger-feeding zone. A cricket corral made out of a piece of plastic will help constrain the prey during feeding time. Recently, i've figured out tong feeding. I would imagine if you had a whole bunch of babies that need to be kept separate, then tupperware it is. But with a single frog, I would suggest getting his final habitat now and not purchasing intermediate ones unless you have other plans for the smaller enclosures.
You don't really need an 'aquarium'. A 'terrarium' will do. Terrariums are much lighter, with thinner glass. Not designed to hold water. This is what you want.

2) My frog eats, on average, a large cricket and a half per day. No, not worth breeding crickets. I buy an amount every week. But, now that i'm feeding one pellet every three days, crickets have now become an optional food. I still have to get crickets for my FBT tank, as that tank will consume eight large crickets a day. Still not an amount that makes breeding worthwhile. Crickets stink and I want to limit or eliminate my usage of them.
Then there is the Mr. Pickles channel. A youtuber has a big ol' pixie frog who will eat over 100 large crickets in a sitting. Even then, I believe this person buys his crickets, as I heard him complaining about the price. A feeding can easily be over ten dollars. For a pixie frog.
If you can figure out how your frog likes to 'tong feed', then you can avoid crickets entirely. Occasional worm purchases for treats. Pellets as a staple.

3) I'd love to hear folks comments about this as well.

I'm just learning too, you asked for experience keepers. I'm not one of them yet. There are a few on this forum.