Makes sense...especially considering we see it in real life NFL from time to time. The Denver trade to Chicago of Cutler comes to mind as well as McNaab. Admittedly, I have done this once in my franchise but have stuck to the houserules for compensation. As an example in my franchise, I traded a 34 year old Jay Cutler who was 89 OVR at the time to the Redskins (after McNaab retired or cut I think) for a late 2nd round pick. I then used my own first round pick to draft a QB who ended up rated 78 OVR with a A potential (got lucky). The guy who I ended up drafting from the 2nd round pick from the Cutler trade was a dude which in the end, is fine. At least it is somewhat realistic in away.
Good luck on your franchise!