Allow users to make collections or folders online of people's creations.
This would allow go to locations for mobile creations, post war airliners, modern tanks etc. making it much easier to find things.
Furthermore, player competitions would be much easier, with the option to allow anyone to add to your collection.
Furthermore, you could have similar hot and new categories for collections as with aircraft - though this would have to apply to the collection itself and not the containing creations.