As far as comparing bazar with Dutch UA, bazar is still better in the long run. Let me show u how :-
Both Dutch & Arabs get 3 sugars. Arabs can sell 5 & keep the happiness benefit while Dutch will only be able to sell 3 at max while keeping the happiness benefit. Some may argue that bazar needs hammer investment but the point is that u r going to build this low tier building in almost all cities so that doesn't matter much later on.
So,based on this argument,there's really no need to improve Arabia UA,right?