1. Partial quantities!!! Now I'm stopped with this issue.
2. Order free sample of product (perfume, fabric etc.) This can be implemented by adding new property to product, and adding button with simular to "add to cart" functionality but with quantity=1 and price=0.
The most needed is first, since customization of quantity requires changing most of main core classes (product, cart, order...) and SQL definitions, making all product updates useless after customization.
Do you have any information about these features? Any plans to implement them?