While I think some things are much better in TS4 than previous games, there's also things I think are worse.
Like for example, I want to see the floor and grid on the upper floor, I don't want it to automatically put down a floor and I can't see what's beneath it, so I can draw out my room or stair area. I don't like that I can't just place or add one single upper floor tile (unless there's a trick I don't know about, when I try to delete one tile, the entire floor deletes), that I have to create a room to place a floor tile in that area, then delete the walls
I think roof is easier in TS4, I didn't use to, until recently when I went back to TS3 and was modifying a roof.
I like that in TS4 we have lots of different size walls, which makes it really easy to make flat roofs.
I don't like in TS4 how fences area done, I don't like that it shows transparent wall when placing them, that messes with me and makes me feel like it's not placing the right fence.
But, I do like that's it's easy to change the fence just by picking a new one and placing your mouse over the existing one, In TS3 you have to delete the existing fence and then re-draw the new fence.
I like that in TS4 we can freely place doors and windows now, I missed that a lot in TS3 because windows are sometimes not on the wall at the height I want, or they are centered on 2-tiles even tho it's a 1-tile window and it won't fit where I want it to go.
In TS4 I like that foundations can be added after the house is build and we don't have to decide where the foundation will go under the house before building it. (That drives me nuts in TS3 because I always forget to do it first, then I'm stuck with a flat house).
I'm sure there's more, but that's what I could think off the top of my head.
