Is it possible to add some hints to closed scenes in the gallery? Even if it's a superficial clue, it would still be great. 

Also, how about unlocking all the scene variations? For example, when receiving scene X, also open its variation with a chastity cage in the gallery, or at least indicate in the tooltip that in the closed scene “the same thing but in a different costume”

UPD: it doesn't matter anymore. I came in to write this post and at the same time updated the game. As a result, in the updated version all the scenes are just immediately open, which makes everything much worse

Yeah, we plan on having a way to see hints for what you're missing still once we consolidate the logic around what constitutes a "scene" or a particular art or animation set. Basically exactly what you're saying there - being able to select an art or animation and toggle on or off the cage variant, or the cumming variant, etc. We have a tool like that on the development side, but getting it in game is a task we have on our plate - once that's in, the gallery won't just be open like it is now.