When making a large base set, one of the things to take into account is the type of subsets that you are going to have put within that base set. With football, you can have a big base set just simply from the size of the teams compared to other sports, but beyond that - still can be some interesting itesm to focus on.
It's a great way to provide some of the important high (and low if you want to) points of the year for the sport in general. Be it large games, changes to the league with expansion decisions, or I guess honouring the number of Hall of Fame attendees, great things to put to cardboard for documenting purposes.
I do like the London American Bowl card much better than the Triple Play-esque Berlin version!
This summary looks a lot worse than I think it will end up being - should change once I get out of the Pro Set football stuffs.