Another thought and an easy one to implement.
A permanent Sanctum merchant. He sells everything that the wandering Outerworld merchant sells but at 20% (or x%) more. Now I have saved up enough for a Power Generator, it is a bit annoying that the merchants seem to be out of stock!
Also some more furniture would be nice. I have two pieces of furniture for my soulrooms and about 30 items that can be placed on top of furniture.
I was also wondering if these items are purely cosmetic or if they actually do something like increase XP earnings.