Well, essentially, abilities are already in the game. Spectacular catch rating, ball carrier moves, etc. So it's not so much that as it is relaying that information to the user. I think that thinking of abilities as "super powers" is overstating it. Players have different skillsets and different abilities in real life. Sure, all players can TRY to hurdle over a defender, but not all have the anticipation or the ability to do it to the extent that some have. Same with spin moves, one handed catches, handwork when fighting off the line, footwork in the pocket, and the list goes on and on.
What I'm more proposing is a quick visual to let us know more about these players without having to go into the ratings every time. Let's use this image as an example:
They tell us that Mathieu is a "Playermaker,' but instead, it would be nice to shrink that name down a bit and create space for "badges" or "icons" that let us know exactly what this player is capable of, but at the same time, keeping it vague to the point where you have to take a chance on them. Change that 95ovr to an A letter grade, and the strategy goes up even more, because then you might have 4 safties with an A grade, and now you have to use the player badges or the physical make up to make your decision. Maybe even give a quick injury history to make it even more deep.
Madden 08's Ability System
I mean, I don't really see what's so unrealistic about showing a more pronounced graphic of what's already in the game. I also don't agree with being able to see the exact rating numbers within Franchise. Keep that for every other mode, but make things more strategic in Franchise. Make Scouts matter. In NBA 2K, they have multiple mock drafts, which put players within the same range most of the time, but each mock has different opinions of a lot of the players. Scouts in Madden should work the same way. Most scouts should agree upon players, but their rankings of the players should differ, if even just slightly, with some scouts recognizing hidden gems and some scouts not being able to recognize busts.
TL;DR - Abilities are already in the game, they just need to be represented on the player's UI. 1-100 ratings, as they are now, take away some strategy in the game. Having more vague letter grades would create a fun meta-game, and that's what franchise mode needs... a meta-game for when you're not on the field playing the actual game.