In a trade/draft trade scenario, IMO, Clay Matthews would be worth the following :
1) A 2nd and a 4th round 2015 draft and a 3rd round pick in the 2016 draft.
or
2) A proven O/D-lineman , not over 28 yrs old, plus a 6th round 2015 draft pick.
or
3) A multi-player deal featuring Clay Matthews and 1 or 2 additional second tier players for a proven D-line starter not over 28 yrs old plus a 4th round 2015 draft pick and a 2016 5th round draft pick.
It is possible to imagine many deals where fair value is given and received without busting the all holy damn cap !
Matthews is and has been a great asset to the Packers, but the bottom line is not sentimentality but what is in the best interest of the Packers. Clay is slowing down from his rocket propelled rushes and sideline "cat like" run pursuits. Moving him inside with Hawk and playing Perry at OLB could refire his production, but will he be able to stay in good health to see it through. I say get the best value you can in a player/draft/player-draft deal.