It would be great to have a Core component for a traditional inventory system.
Something like what you see in almost all games in which you open your inventory and see a grid of items with a limited number of slots. Players can easily select, equip, or use any item in the inventory. This is a fairly complex item to hand code, so it would be a great benefit to the Core system to have something out-of-the-box that developers can use.
( I did see the inventory example in Core Royal, but that is pretty far off from your traditional inventory system. )