I am especially pleased with recent updates, but I would like more use for experience points. They currently only upgrade your level and unlock decorations. If you added more use for xp, such as achievements, I think it would cause players to be more determined to reach higher levels, and you could possibly add small little experience bags to the shop every now and again in special offers. I first encountered the idea many years ago, so I believe many players would celebrate such an update. Of course, if there is a reason you haven't done so and never will, that sits fine with me.