Businesses normally cycle out inventory that isn't selling as well, so my idea is to have it so most stores will cycle out a portion (maybe 10-20%?) of their inventory once a week. This would prevent the buildup of things that there's not as much interest in, making for some amount of player convenience, while also making sense from an IC business perspective.
In the case of ones that require a crate to restock, I think that's fine. The idea is more to just encourage inventory movement in a way that makes sense IC and reduces the smallworlding feel of the store system as it is.
Alternatively, being able to request certain items/materials, even if there's some amount of upcharge for a 'special order' would be a great help, especially when it comes to stores that see almost no movement (looking at you, store that requires a license for purchases and only restocks with crates).
Thoughts?