It looks like you're really getting into a nice groove, John.
Roberto's class, from the videos I've seen, looks pretty remedial and beyond your skill set, but I'm kind of surprised he didn't try to up sell you on some one-on-one training. That's fantastic that he's letting you sit on a class for free. Please take plenty of pictures and tell us all about it
I have to admit, I'm not too fond of the dessert pizza concept. Savory bread + sweet stuff seems off to me. I know that the Nutella jar has a photo of it being spread on bread, but, that, to me, is more of a savory PB/J sandwich kind of thing, then a dessert. Max Brenner, a well known NYC chocolatier does a chocolate pizza, but it's with a cookie-ish crust. If I ever did a dessert pizza myself, I'd probably do a special sweet dough. This all being said... with the caramelized sugar and the fillings you're working with, I'd probably devour a slice of it.
It's sounds like the dessert pizza is really working for you, but how about stretching the dough a little thinner and brushing the baked crust with melted butter? A thinner stretch and some butter might bring it a little more into the pastry realm than the bread arena. Just an idea.