Something that would be helpful is a "sort by size/shape" function, so i don't have to remember, say, which building is 3x4 and which is 2x3 and i can quickly find something to put in the weird shape I just created.
I'd love to see more consistent coloration in the building-free zone map. pubs and distilleries are orange which is great but other entertainments are red like production and residential buildings, which makes it difficult to see at a glance if you've got your block set up right.
a "newly available" building sort feature would be great if it could pop right after you buy a tech or hit a necessary milestone. even just a "you have new things available to build," because sometimes you buy the tech but don't have xyz other condition met so you wouldn't look for something that's not available yet.
I'm not 100% sold on the sort by size idea, but I like the others. (Just my opinion) Maybe multi-purpose buildings could have colored stripes if they are both housing and entertainment.
Part of the appeal of this game (to me) is that you have to figure out what buildings are available when- either on your own, or you can read it in the encyclopedia, like minecraft. So, like minecraft, I think an achievement screen would be helpful because then you get some idea to the types of major goals you could be thinking about, without being told expressly what you need to do to get there.
maybe the size-sort thing could be addressed by a customizable "favorites" section in the build menu