I have one guy who started out at WE 24, overall rating of 505 as a freshman.  I signed him at a time when my team's defense, spd and ath were about as crappy as they could get and Lowe offered me an upgrade in the cores.   whatifsports.com/hd/PlayerProfile/Ratings.aspx

So I started him on Day One and he's never lost his starting position. Today his overall is 618 as a junior, for an improvement to date of 113.  He started out with a PER in the high 30s so I haven't let him shoot many 3's.   This season he averaged 7.7 ppg, 5.2 apg.  

I had a PF start out with 26 WE, and overall 470. I started him as a Freshman because he had good core values and high improvement. At the end of the 2nd year regular season, he is now at 40 WE and overall 594. He played 22 minutes per game as a Freshman, and was conference Freshman of the year, and this year he is playing 24 minutes per game. He has improved by 58 points this year during the 26 game regular season. And his WE has improved by 7 points this year, so I guess it must have improved by 7 as a Freshman. So, he did way better than  the "rule of thumb" I mentioned in an earlier thread. I think a lot depends on minutes and if they start. He has started every game both years.