Much as I love browsing on the site, it becomes annoying when, especially while looking at sales, titles that I already own, or I am just not interest in, pop up. It really hurts the discoverability of other games when I have to first trudge through the same few dozens I know inside and out at this point; this is likely going to be even more valid for a lot of people now, with the huge swaths of additions from the RJE Bundle.
Just as it takes a few clicks to add a game to a collection, same should apply to add it to a personal blacklist, and if the games can't be made to disappear from the user's searches altogether, at least have them sport a label (like a small icon either over or under the thumbnail) that signals the user to skip to the next item. It could be done in the form of a simple additional option in the same window used to add games to collections.
Similarly, an option should be given to allow already owned games to not appear or, at least, have a label that signals them already being in the user's library.
Since we are at it, I couldn't help but observe what a chore is to remove a game from a collection: you have to open the collection, find the game in there (the earlier it was added, the longer it will take to reach it), and finally remove it. To top it off, it can only be made if the collection is set in grid mode, as list mode doesn't even display the removal option. Methods for easier management in this sense would be appreciated.
I think Itch should treasure the exposure given by the RJE Bundle to step their game up. Options like those would be huge QOL improvements.