Were you not here for Destiny 1? If not, I'll explain it to you. In Destiny 1, kiosks were seperate storage units from vaults that contained already unlocked exotics. This allowed players who were low on vault space to delete some of their less used exotics, while still having them available whenever they wanted to use them. This was great because it allowed much better organization of exotics. Unfortunately, it was never possible for legendary weapons. Since legendary weapons had random rolls, you couldn't have a kiosk for them. They would need to have a set roll to be in a kiosk because you don't actually store any weapons in them like you do with vaults. I was saying that I expected kiosks for legendary weapons in Destiny 2 because they now have set rolls.

just shows you what you have collected overall. they had it in d1 and it was really great. would help free up vault space

Good idea. A book filled with statistics about your guardian. That sounds like it would be really cool to look at and keep track of. The emblems are cool, but you can only hold a maximum of ten of them, so if you want too look up more you have to go to the vault. Now that you mention grimoire, I wanted to mention that I have an idea that would help add more lore in the game. They could add a book that would contain data on every object you've scanned, as well as every exotic you've collected. Right now you can look at lore for your exotics, but only if you have them in your inventory. This book would allow all of that data to be in one place. For scannable objects, it would have lore that would go more in depth on the topic. Kind of like a dead ghost from Destiny 1, but with audio from your ghost that would introduce the topic. This would actually be better than dead ghosts from Destiny 1 because you could learn a little bit of information right away, and then see it in the in-game book when you're finished with your activity.