From an organizational standpoint, I think it's important to re-up your homegrown All-Pros. I also think it's important to pay them near market value (assuming it doesn't destroy your cap).
Last year, PC/JS said extending Kam was their top priority (even over getting Harvin). I believe them, and I don't think this was just lip service. People were also surprised he got a market value contract. But there's a reason for this. Rewarding your top homegrown talent creates an important model for the other young players to follow: if you bust your butt and become the best at your position, you'll be rewarded handsomely. This is especially important for a team that relies on maximizing the development of late round picks, and I believe this is a big part of Pete's philosophy. Therefore, I think their top priority heading into this off-season is extending Sherman and Thomas, and I bet Pete talks a bunch about the positive impact of this on their organization at their joint press conference.
I think Bennett is a nice-to-have. I certainly hope they can work it out with him, but I sort of feel like the team could probably keep finding bargain pass rushers on short-term deals year-after-year. Rememeber, there was no market for Avril, Bennett, Abraham and Osi last year. Would your rather committ to Bennett for $8+ million or get someone like Jared Allen for $4-5?