Every decent online storefront's catalogue should have a few things.
GOG catalogue used to have proper genre based filters. But since the website overhaul those are missing. Now one can use the name of genres on the search bar and get the same results, yet this is not the same as seeing the different filters organised on a bar.

Also what the catalogue really needs is more theme/narrative based tags. It is a pain to browse the store and discover titles. Eye-candy is fine, but functionality is much more important.

The feature which suggests similar games based on the current game you are checking is also very limited, and when it shows five suggested games all of which you already own it makes this mostly useless.

Is it even any use pointing these things out? I don't know.
Maybe things will improve. Maybe the review section will see changes for better.
Maybe.

EDIT: minor changes. Also, is the forum eating my thread?
is the forum eating the thread?
Is the forum eating this thread?

Also I think the GOG staff could do a staff picks sort of thing to feature to highlight lesser known games.

And I really miss GOGMixes. Steam has curated collection. And GOG removed GOGMixes.

This is important.

Those were really helpful, I wish they would bring GOGMixes back.