Looking at your GBs, I like all the ones you currently have. There are some players that might say the Hagia and Dresden could go, but I really like both of them. Of the GBs that you have full BPs for, I would go with the Alcatraz first, unless you do a lot of quest looping with the recurring quests. Once you get the Alcatraz, you can get rid of most or all of your barracks other than the Rogue Hideouts. Unattached units from GE should be enough to keep you supplied with regular troops. It will also alleviate the need for a lot of cultural buildings/decorations because of the Happiness it provides. If you do much quest looping, then the Chateau moves up in importance, because it increases your coin/supply/goods/medals income from quests. I would put the "fat albert" (LOL) ahead of the Deal and Capitol because you don't have a lot of supply buildings, and its boost added to the LoA's would maximize your output from the ones you do have. Deal is big, but it will help with the plundering problem, so if you have the room at some point, it would be okay to build. I wouldn't bother with the Capitol at all. You have plenty of houses, so you probably don't need the population, and it doesn't give enough supplies to make it worthwhile.
Now to your special/event buildings. Ones I would definitely keep are the Black Tower, Rosarium, Royal Cascade and Lord's Manor. Ones I would definitely get rid of are the Santa's Workshop, Hedge Maze and Shrine of Inspiration. I'm on the fence about the Bazaar and Luau. Ironically, although they're almost identical I really like the Bazaar and don't like the Luau. Go figure.
I am not a fan of the set pieces, but would definitely keep the King/Queen statues with the Garden Ruins because it's fairly small. Most of the rest give decent stuff, but they're big, plunderable and they can't be moved easily.