I think a very useful function would be one that allows you to update the quantity to be added to the basket based on the 'Name & Numbers' list you have filled in.
I enclose a screenshot for reference.
Each item added implies an increase of one unit in the cart.
I think this function is very useful to avoid errors or inconsistencies in orders, this happens to us very often unfortunately because it is not very intuitive for the customer.
I hope you will consider this feature