Did a bit of searching with some basic keywords, came up with nothing. So figured I'd open a new topic.
A method of watching/following other players would be a great tool imho. Say I really enjoy one person's creations. I can't really rely on FP or "by-date FP" because of obvious reasons. Actively searching could get annoying, especially if you forget how to spell their name exactly.
Having the ability to watch a player's submissions would give us a few different things. The main feature, is a place to view recent submissions from who you're watching. See the fave star up on the search bar? Adding a 3rd button with say... an eye? Or maybe a heart (will explain this suggestion in next para)? Clicking this will display only submissions from people who you follow, and the notifications can be deleted without affecting their or your saves.
Now to explain the heart: There is a possibility this could be set up instead as a friend system, where players are notified of their friends' submissions. This would also open up logical reason to have a form of messaging system. The Creations forum seems to be tied in well with the game, so I assume that the same can be done for the PM system here, linking the game to the site in that regard as well.
And perhaps just to top this idea off, maybe the setup. Adding another new idea here as well as a potential format. The new page on TPT could have 3 columns of submissions, as to make room for this last idea: activity feed. In the activity feed, things like what your friends have added to favorites could appear, as to easily see what the people you have friended/followed are currently interested in. Could be set up similar to the comment feed on the side of submissions before opening them.
There are easily hundreds of tangents I could go on, but I think I hit some of the major ones. I'm sure a friend list has been suggested, but that thought kind of randomly popped up while writing the first couple paragraphs.
TPT would become a social network
That is actually one of the other tangents I was thinking of going down, but I didn't want to start suggesting anything radically different in case it wasn't the path you would want TPT to go down. But making it into a social network could possibly be one of the biggest and most important changes, if done correctly.