[KBLover]

I think players should have career curves where their ability changes regardless of their performance or at least performance should just be a "modifier" instead of the sole determination. Just because someone has a good or bad year (or game) doesn't mean their actual skills have increased/decreased.

I think the growth/decline of skills should be governed mostly by age and potential, but have different aging curves. Some guys peak early and drop as fast, some are "sleepers" and take long, but break out big when they "wake up", etc.

Also, I'd like to see skill by skill potential/progression. I'm guessing there's some things a young QB develops faster in (like throwing arm) while other things come more with experience (like AWR).

Throw in things like needing playing time to develop fully (make progression occur once a year for everyone, but then also once every X downs played as well).

Things like this would really help flesh out player development, imo.