To me the volume of cards is the most important. that is why I have been chasing cheap commons. The more the merrier
Getting a card of each player would be nice but some of the older stuff is real hard to come by. Lot of them are just Nebraska issued stuff. That is low on the list. but you have to keep looking or you will not find them.
Dallascardboys (COMC) has a lot of cards and oddball stuff that I need. A lot at $2.75 range that IMO should be in the $1.75 range. He does not run sale (only a few time) and rejects most offers. I did break down and purchase 15 or more at one time when he lowed his price by 10% for a while.
Getting 1,000 Ahman cards is high on the list.