norma, I too have gone down this path of trying bread enhancers and dough conditioners in my pizza dough. My goal was to try to achieve effects that were close to what bromate does, without the potential health risk. Ultimately I have ended up not preferring to use any of them, but I think it will be a fun experiment for you and I would love to hear your findings and descriptions of what they do. This was many years ago for me, and honestly I have forgotten what some of these things end up doing to the crust of a pizza dough. A few things I do remember.
I found that different ingredients seemed to do different things at different baking temperatures.
I found that even tiny amounts of most of these conditioners seemed to make big changes in the dough, so recommended dosages for bread often produced too much "effect" for pizza.
My suggestion is to try one at a time and see what you like, then make your blend from there.
I remember one of my least favorite enhancers was lecthin, which actually took away from the textures I associate with a good pizza dough. If I remember correctly it made it more dense, and almost a little soggy.
Bakers grade non fat dry milk was one of the best ones. It actually did produce a bromate-like lightness, but at the expense of also adding a very crispy texture and a little extra browning. This is one of the things that I actually liked way better for my high temp 2-3 minute bake pizzas, which can sometimes need a little help in the crisp department. For normal 550 temp pizzas it added too much crisp for me. The milk definitely adds a very nice flavor. I was using tiny amounts....less than 1% and I could still taste the flavor enhancement.
Ascorbic acid didn't seem to do much, maybe a little added lightness, but nothing like what bromate can do. At one point I tried using quite a bit of it, as I wasn't really seeing much from it in recommended dosages. When I did try the higher percentages it just made the dough gummy.
Vital wheat gluten added a bit of air to the dough and allowed it to rise more, but the expense of making the pizza chewy, which is not what I am after. I have no problem achieving chewy by screwing up the mix or the proof
Diastatic malt powder added browning for sure, and I liked how it made a flour without it like caputo more easily adapted to normal temp ovens. The change in texture did not seem to be dramatic.
I have never played around with gelatin, but I am interested in your findings. Also, another ingredient that comes up in these bread enhancers from time to time is ground powdered ginger, if you want to add that to your list.
I hope I didn't discourage you, as I would love to hear back what your take on all of this is. Thanks norma, and have fun experimenting!