I'd love to get to a point where I can scope my jam designs as compact as this. One screen design is really a great jam strategy!
I think the items piling up haphazardly leans into the tension and chaos of the situation. Since it appears that successfully placing treasure in the hoard or down the hole are equivalent for the dragon's patience (timer), the next item that is picked up doesn't really seem to matter that much, SO if we automatically picked up a new item when near the pile, that might be a nice QoL design.
I tend to dislike memory mechanics for some reason, likely skill issue, but I had some fun with it this time, trying to come up with shorthands to help me remember at least some of the rules list.
It could be fun if the player had action options: place or throw. Sounds really fun to be able to quickly throw treasure down the hole from a distance. A possible interesting constraint could be throwing wanted treasure into the hoard gets you burned as the dragon doesn't want its precious stuff dented?
Had fun during and after play! Great work, keep at it!