I like your thinking on this, but from the vibes I've picked up, they'd be afraid to even go that far. It would probably require more programming to come up with this alternate presentation of invisible AI players, as simple as it sounds, than to show shot tracers (they're already built into the game for simultaneous play anyway). I wish they could come up with something more representative in this regard though.
I've always wondered why they couldn't allow you to play your career mode rounds with one of licensed pros animations if they happened to be in your group, and especially if they happen to be tied with you for a playoff. I would think that would allow EA to get more out of the license fee they're already paying the licensed pro?