He never relied on speed and he had over 700 yds receiving in our anemic offense last year. By default he'd be no worse than our 2nd or 3rd receiver.
As for Jared Allen, he's going to go into the HOF, he was one of the best past rushers of the decade after maybe only Julius Peppers and Dwight Freeney and Allen is an end.
He got 700 yards because he was our only quasi-qualified WR (Outside of Torrey Smith who barely tried the entire year) so we didn't have anyone else to throw the ball at. Speed is overrated for a WR, he ran like a 4.8 out of college, but he got separation even as recently as last year which he didn't even come close to getting this season. No separation means he should go. They should give the spot to someone younger.
Jared Allen will be a HOF, but he ain't done anything of note this year and he should go too. Past performance means nothing right now. He had 2 sacks this whole year. He ain't retiring because his body hurt. He knows he's terrible now. He couldn't even ride the bench for any team with sense. The NFL doesn't sign vets for lockerroom presence like the NBA does.