He plays the most snaps on the defensive line each game and makes an impact. It's to considered "overpaying" if the guy makes an impact. Cletidus Hunt was overpaying for a lineman. Vonnie Holiday was overpaying for a lineman. Raji should be properly compensated for the role he plays on defense.
Just because a guy has an impact doesn't mean you're not overpaying them. Finley has an impact, but I think most would agree making him the top paid TE in the NFL would be overpaying. They don't have to be a bust like Hunt to be overpaid. And just because a guy makes an impact doesn't mean fiscal responsibility can be thrown out.
I think the real issue is whether there is a gap, and how much, between what Raji thinks "properly compensated" is and what the Packers think it is.
There's a lot more involved in the decision making process than whether they like Raji and want to keep him. I realize fantasy football is different than the real thing of course, but an auction league analogy would still apply. A team gets "X" amount of dollars to spend on their team. They have to decide how to best distribute that money to put together a winning team. Sometimes that involves making tough decisions and letting people go who you don't want to. Just the nature of the business.
Paying Raji, at probably our deepest position on the team, would be at the expense of letting other players walk at other positions.