Darvond: The store browser link didn't quite work for me, as it failed to filter out the titles. It only works if you manually toggle it, so eh you know, another day on GOG's half baked store interface.
The link works as intended for me.
The store filter sometimes "forgets" the checkboxes on the left however, especially if you refresh the page. In that case you need to check/uncheck one of them again.
I usually set it to [url=https://www.gog.com/en/games?order=desc:discount&discounted=true&wishlist=true]this[/url] to get started.
It may be half baked, but it's better than the wishlist.