I have mostly just decorated my houses using different glitches that blend into the decor such as adding a statue in a fountain or ships in water.
In my ice house I do have a ship wreck. I put a ship partially in a large rock and floated wooden planks around it.
While waiting on Azteca, I decided to craft every piece of furniture in the spiral not counting the housing games. I put all those items in my dragon fjord house. I am now in the process of crafting the Khrysalis furniture. The problem is not having the space to place them inside the house. I got the item count high enough just no room left In house. Will have to make a few adjustments.
I also have several houses on my wizards that are just storage for pets and furniture. For some reason I find it difficult to sell housing items.
At the Island getaway, I turned it into a resort with a dojo. Many little blue cyclops like to vacation there on the beach. I once met someone called Morgrim, who had the Death House decorated as a pet museum. There were pets up on pedestals and in separate rooms, or corrals outside. There was one kind of pet in each place, a room for spiders, corral for dragons etc.. At the time he had almost all the kinds of pets that were available.