I really like the direction you are going on the POs, but right now, one major flaw is the lack of any kind of reporting on them.
I would like to be able to export all my POs to a csv file. Each row would have only 1 item from the PO on it and then reference, PO #, Dates, Tracking, Vendor, etc. on it. This would repeat for each item. Shipping charges would also be on their own line.
I would like to be able to have the option to download all POs or just the selected ones.