At the very least we could've had some unique and useful options in our home, like a prominent place to show off those Elder Scrolls we've collected throughout the story. The ability to get rid of the master bedroom upstairs and still make something useful out of the room if you decide to build the bedroom wing.
The ability to build any wing anywhere would've added serious improvements to this mod. As it stands now, the northern wing is mostly useless to me in a normal home, and I'm forced to forgo the awesome greenhouse because I have a family.
Furthermore, I've seen other good suggestions. Show us spots in our home where we can put stuff, but let us decide what to put there! Want mannequins all around your house? No problem! Want barrels instead? No problem! Would you rather have some (working!) display cases? Not a problem either!
Hang anything on the wall that can be hung there. Even if they tell you where you are allowed to hang stuff, it's still better than what we got. A couple of things will always be in the same place of course... can't really choose where to hang a chandelier and such.
If we had those things, I wouldn't complain that your house always looks roughly the same on the outside. I'm aware that if you truly want to be thematic, it's quite hard to make a house look different on the outside and yet fit with the interior. It can be done though, especially if people get to choose their own interior.
I just wanted to add my two cents to the collective disappointment.
PS I should really also complain about the fact that I had to install a mod to get my wife to move to our new house.