Instead of changing how the king picks his item, why not explain the mechanics IN GAME?

[vagrant harness]

The problem with how the king works is not how he chooses his items (currently: only from items that are set to go directly to the shelf). It's simply that anyone who plays the game without using Discord will not understand the mechanic, because nothing tells you this within the game itself.

Instead, why not add a little crown symbol over the self/bin icon that lights up when the shelf mode is selected. Hovering over it (or tapping it) would have a little pop-up that tells players, in game, that only items set to shelf mode can be selected by the King when he shows up. This solves all of the problems. Another option would be to have a little crown icon on items in your inventory that lights up if the King can select it. Again, hovering over it (or tapping it) could have a little pop-up that explains that it is or is not valid, and if it's not valid it could then explain why. Actually communicating this stuff in game would go a long way to dispelling confusion on the mechanic.

Alternatively, if we absolutely must have a system where it goes to being a complete crapshoot which item he'll choose, could you at least add a way to instantly pull all shiny items off of your shelves? It's not too bad for me, since I'm very fastidious about what items go out, and where, but for sane people this is just adding unwanted micromanagement in a game that already has a lot of balls to juggle. A little QOL to go with the extra hassle would be nice.

Another idea: Add a 'Help' button to the menu, and have pages that explain things like the King's visits, how Flashback quests work, any other obscure information only known to Discord users, as well as a summary of all of the tutorials (for anyone who forgets something). Try to keep information about how to play the game contained within the game, so that people don't have to exit the game to figure out a mechanic. Every time a player does that, you're losing their immersion and creating 'stop' points. A good, self contained help system is very useful for onboarding new players and maintaining player retention.