Well, first, every player is largely done developing by their 5th year so how you see players 0-4 seasons is what you're seeking. If you're not trading for those types, it doesn't matter. Second, players have a pretty straighforward development pattern. So, if that 3rd-4th year pro has improved 8, 4 and 2 points in a category over the last three seasons, he's pretty much done improving. Third, if you're looking to trade for 1st-2nd year pros, look at their draft positions or signging bonuses. Unless the guy you're dealing with is a 'tard, a high pick or big signing bonus is pretty good. If he's trying to sell you a 3rd round pick or 375k IFA as a future HOFer, he's probably full of ****.