I agree completely on the 2k/Madden 08 ability statement. And I think using Madden 08 as the reference is even better because of the fact it is EA's own product.
The reason 2K's abilities "popped" is because the developers gave every player in the game roughly the same ratings. All of the generic players (non star) had the same base speed, strength, consistency, agility, catching, etc. ratings. All of your tiered players also had similar ratings that would increase slightly depending on the talent level (Gold players are going to be naturally stronger and faster than silvers, Silvers are better than Bronze, etc). I remember that 08 had abilities but I don't remember those abilities giving players ability specific animations outside of the "Spectacular Catch" animation, it just meant the generic animations were more likely to trigger.
In 2K the abilities gave players specific animations. So if your player had the ability, he'd do things that those without that ability simply could not do. For example IIRC Madden 08 did have a stiff arm ability but the only thing that would happen is the icon would flash when a successful stiff arm triggered. In 2K8 the ability is called "Arm of Steel", and players with the ability will perform a significantly better stiff arm. The animation is faster and different than a normal stiff arm animation. The important thing here is I can go into the game and Hex edit a player to have a 99 Stiff arm rating, and he'll stiff arm guys all day. But if I don't give him the Arm of Steel ability, he will never be able to trigger the best stiff arm animation.
The Animation is what's important because that's what truly differentiates my guy's Stiff arm from yours.
I think the way Madden has it set up is at a 90 rating you get access to other animations. That's lame, because an 89 rating shouldn't be that much weaker than a 90 rating. Instead try making the base rating for all players who don't have a legit stiff arm a 78, and give guys who do have a stiff arm the 90 rating. That way if a guy has it, he does; and if he doesn't, he doesn't.