I almost want to do a ranking of the UBs in the game, but most of them feel to me like the Tlachtli, which is kind of the jimmies on the sundae of the Aztec civilization, but ones you never asked for and which don't actually go with the sundae in the ways you might hope (In the case of the Aztecs, they're already given a bonus to how good amenities are, and their whole gameplan is to get as many luxes as they can to max that out, kill enemies to get workers, and use those workers to speed up district construction. So at first glance the Tlachtli looks solid - Aztec are all about Amenities, right? And this is an Amenity-granting building that also gives you faith and Great General points! Except that the Amenity comes from entertainment and so doesn't help your units, the district is unnecessary with your other bonuses, faith likely isn't a big enough part of your gameplan for an extra +2 to matter, and you're better off getting your GG points by building Encampments. If you're lucky enough to take over a city with an already-constructed Entertainment district, sure, build one, for the Era score if nothing else, but you're unlikely to go out of your way for this. Tsikhe are of course even worse here, requiring a lot of investment in hard-building for limited return, but at least don't require a new district for them. The Queen's Biblioteque is powerful but also requires you to pass on any other L2 Government Plaza building. But yeah, the Ordu, Basilikoi Paides, Sukiennice and Marae are all solid and central to how their civs operate. The Grand Bazaar is also pure value, giving you bonuses for something you'll probably build a lot of anyway, and if you weren't going to, well, the extra amenities synergize well enough with the Ottoman gameplan that you might reach a little and build more banks than you otherwise would.