I've got two questions regarding crust browning and flavor.
1: Are there any ways to control the bitterness and other flavors of the Maillard effects via formula?
2: Do sugar types matter for the Maillard reaction flavor?
Those are interesting questions. Off the top of my head, I would say that the answer to your first question is yes. The browning of the crust of a baked pizza comes from several sources: residual natural sugars derived enzymatically from the flour and remaining after feeding the yeast, any hydrolyzed sugars (like hydrolyzed sucrose added to the dough) and also remaining after feeding the yeast, caramelization, denaturing of the protein in the flour, and the Maillard reactions. In your case, you did not add sucrose (ordinary table sugar) to the dough but you did add honey. But if the objective is to reduce the above effects, so that you don't end up with a bitter flavor in the crust, you could use an unmalted flour and you would not add a diastatic malt powder. But you can't ignore the need for sugars, in whatever forms, to feed the yeast over a long fermentation period such as you have been using. Otherwise, the yeast might run out of food. So, you may need an added form of sugar, whether it is sucrose or honey, and maybe you could tolerate a small amount of diastatic malt powder if the amounts of sucrose or honey are on the low side (although it is simply easier to just increase the amount of the added forms of sugar). You could also use a nondiastatic form of malt, which is a form of sweetener. The overall objective would be to make sure that there is enough food for the yeast over the full fermentation period and with just the right amount of residual sugars to participate in the Maillard and other reactions and yield the desired flavor profile.
With respect to your second question, I suspect that sugar types can affect the Maillard reactions to the extent that the simple (reducing) sugars that make up the sweeteners are not the same or may require hydrolyzing. For example, honey is 38% fructose, 31% glucose, 1% sucrose, 17% water, 13% other. The simple sugars for honey are available immediately to participate in the fermentation process. By contrast, sucrose needs to be hydrolyzed to glucose and fructose before those sugars can be used. If sucrose is just left to sit there unmolested, years can go by without hydrolysis taking place. What is needed is an enzyme such as sucrase or an acid component of some form. Even then, it takes some time for hydrolysis to take place. So, it is possible, I suppose, that the Maillard reactions may not be identical for honey and sucrose. And if you were to use a different sweetener, such as molasses, for example, which comprises 29% sucrose, 13% fructose, 12% glucose, 22% water, 24% other, the Maillard reactions may be even more different.
In your case, with only 0.5% honey, I don't see that as a source of bitterness. Caramelization of sugars can sometimes lead to bitterness if there is overcaramelization of the sugars as can overdenaturing of the protein in the flour. These effects might occur from baking the pizza too long, which might be easy to do with a BlackStone unit if not managed to avoid these effects.
If you would like to read more about the Maillard reactions and related matters, you might want to read the Maillard section of the article at http://www.classofoods.com/page2_3.html
As I was composing this reply, I see that Mitch and Steve weighed in on the subject. If you end up with unbaked flour on your skin, you can end up with a bitter tastes as Mitch and Steve noted.