I have had pizza parties with multiple Kegs rolling. It's doable. The thing is with Kamados, they can get hotter than blue blazes but that doesn't work on a big ol' pizza unless you want a black crust and underdone dough with luke warm cheese, lol. The sweet spot on a kamado is about 650° on the stone. We actually have a "method" of cooking pizzas on the keg. We make our dough and shape it and place it onto a parchment paper lined pizza pan, trim off the edges otherwise it'll burn (parchment paper, not dough). Sauce, cheese and top it and take it to the keg. Slide it onto the pizza stone by pulling the parchment paper off of the pan. Once the dough sets up (about 3 minutes) we slide the paper out from underneath the dough and then let it ride the stone to get nice and brown. Rotate it to cook even as needed. All 3 of my kegs cook hotter in the back, not sure why.
The UUNI would be excellent for parties as long as you're doing individual pies for each guest. I would involve them in making the pies though, saves you time and lets them make it the way they want. I would make the skins for them, let them sauce, cheese and top them in "pizza bar" fashion. Once they've made their pie, bring it out to the UUNI (or blackstone, etc.) and fire it off for them. I go a little overboard, I have little pizza boxes (10 inch) that I put the pies in once they're done
I blame Restaurant Depot for that, lol!