I'd like more customization options; the ability to edit draft picks (at least the names, country, height, weight, etc); the ability to relocate a team (like Madden had (has?) after a season, building the stadium, etc. Also, I can't believe that they haven't set up a teambuilder function like NCAA has; I could have sworn every EA game would have that by now!!!
More team specific strategy. I'd love if each team had a set of sliders so that playing a team wouldn't be just playing the standard AI, but individual team strategy. That would add a ton to those of us that play offline!! Maybe add coaches that have a certain style; then it would change depending on which coach you hire.
More team history options. When I play through a franchise, I track all my own stuff; but why can't the game do a better job of this for me. Have a place that shows my stats, headlines, highlights, photos, transactions, trophies, etc. Allow me to upload stuff to my computer. Sort of like a dynasty manager in game. I have a giant hard-drive on the Elite; let me use it!!