Feature that exists in some games, but sadly most often left out by game designers.
Rare recipes - items which allow to craft items.
They could be either 'learnable' - learning recipe consumes the recipe item and makes our glitch remember it forever, or not - just having recipe would allow to craft.
This would allow to add whole lot of item drops that are both rare and have actual use (eg. dolls are rare but have just collector value).
- Rare dishes with special effects
- Rare beans for rare trees (can be just ordinary trees with different skin)
- Rare eggs for rare animals (can be just ordinary animals with different skin)
- Rare potions / tinctures (potion of avarice has already a recipe that is fairly hard to get)
- Rare tools that have yet further increased durability or have increased random item drops, or have chance to add some special buff
- Rare house decorations for incoming house upgrade system
The added possibilities are almost limitless.
Also, possibly the recipe copying skill(s) which would allow to copy a recipe using crazy amount of resources, to prevent the recipes from becoming too common, like 5k paper and 100 diamonds :P
Then the vendors could offer recipe book item - much like toolbox, only for recipes.
The problem with this system is that it would add some very tangible goals (grind) and that might interfere with sandbox-ness of the game, but i think it would not be a problem for people with real sandbox spirit?
Thoughts?