This may sound outlandish and would never happen in all likely-hood.(at least in an EA game)
My suggestion is to have no visible ratings to the player. This would create the realism of uncertainty that the NFL has, you could draft a rookie that you expect nothing out of and one day your starter goes down, you are forced to put your rookie in. He ends up lighting it up. This would create a very realistic aspect. Instead of attributes, Players are given grades of how your team's scout views them in your system. For example established super stars are A+ stars A Great players A- etc. The talent that your scouts have will lead to better or worse players for your team. You will have to judge players based on your scouts opinion nfl stats and college stats, (hell if they wanted to be even more realistic they could include video game 'highlights'), opinions around the league, opions in the media, and fans. But of course with the aspect of realism, scouts and every one else will ultimately miss some players, which could go untouched or turn into legends for your team. For college players scouts will grade players as to what they believe they could turn into. But even though a player is graded to be an A he could turn into an akili smith
Behind the scenes players will have been already rated by the game makers and given skills.
But these skills are just the base as progression depends on how much your players improves statistically from one year to another. Things that can deter progression are injuries, aging or having a bad year.
This system of unknown would create the most challenging and the most deep sports game ever.
Critique. applaude. whatever. its an idea i needed to get off my chest

. It's more about pleasing fans then being right.
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