It could work like this....when creating a new class you could select a number of "storyline" players. EA could set the max/min number of storyline players to whatever (say.....4-16 as a range). There could be a min/max on OFF vs DEF players (say....of the 4-16....it has to be somewhere between 25%-75% to a 50%-50% split).
That keeps a few realistic parameters but allows you enough control to slant the class to one side of the ball and also allows you create stacked vs weak drafts.
They could then create a few hundred(several hundred?) mock storylines which get randomly assigned to your 4-16 storyline players. There could be soem specific ones for each position (say..a few storylines at each position and each player type at that position-so QB>Field General might have 5-10 really indepth storylines that everyone would see eventually and then several more generalized random ones).
You could create only storyline players, you CPU generate the whole thing with editing options, whatever mix of manual/automated that you like.
There could also be "draft types" or something....kind of like the player types. When creating players, and especially non storyline players, you set their draft type to: random, star, superstar, specialist, hidden gem(certain attributes specific to his position grow faster than projected), project player(develops ONLY in the right scheme when he fits the proper player type for that team at his position), bust, surprise.....the types could be random.
We could community share them. I could create 1 class, share it with my buddy and he could add class 2 and so on.
Options are limitless.