Wow. Sounds like you and Spitfire have your nutrition all planned out.
We tried gardening but ended up mostly giving up on it. The soil here isn't too good. Lots of rocks and spirea roots. Spirea makes a beautiful hedge, but the problem is it doesn't stay there. It's invasive and send out roots all over the place and little plants sprout up overnight where you don't want them. You have to keep mowing them down and digging them up, and my husband has spent hours doing that. Last summer he tried growing collards, endives, and mustard greens in pots, but the only thing that did well was the mustard. The summers are short here but lots of people garden and have some success with various things. We used to have mint growing wild, and we also have raspberries growing wild in the back alley even though I don't seem to be able to grow them in our yard. Go figure.
This year my husband cooked up a fresh kabocha squash for all of us. It's Puff's favorite squash and I tried some of it myself and liked it -- a lot. So my husband saved the seeds, dug up some dirt from the yard, and planted them in an old barbecue. A little late in the season so I think he's going to be disappointed, but what the heck. We'll see what happens.
The way she's eating and shedding, it sounds like Spitfire is going to grow really fast. You're lucky you've got one that's not a finicky eater. I am amazed that she can catch flies. Our beardie has trouble catching things that jump and crawl (crickets and roaches), let alone anything that can fly. He once caught a UFI (Unidentified Flying Insect) that wandered into his tank, apparently when we had the lid off. He scarfed it up before I had a chance to get a good look at it, but that sort of thing definitely doesn't happen very often.
My husband likes dandelion greens, but I don't. Like you say, too bitter. Some people say that they're not so bad if you pick them when they're little, but they get really big really fast around here in the summer with all the extra daylight. We aren't buying too many greens for Puff lately because we have a whole yard full of dandelions, which are supposed to be a good staple for beardies. Puff doesn't think so, but he's not good with any other greens either.
Oops. TLDR.