To avoid filling the market with decorations that are sometimes too "random" or limited to specific groups and not very connected to the game, I propose to hold themed contests in which users can upload UGC on the theme chosen by the staff in order to direct the creation for what can really be useful to the game. For example: in November you can hold a contest on the creation of Christmas-related UGC and select 3 to 5 players who will be able to "mint" them and sell them as now (and possibly win further prizes). Even better if the selling price is recommended by the staff (now too many UGC have exaggerated prices for no particular reason).

This way you have more specific control and can represent a nice challenge for the players themselves.

Thanks!