Trocheck is/was a better player when he signed though. Trocheck didn't have a good year, but his 59 points this past season would have been Bennett's career high. In fact Bennett's 51 points this year (which is his career best) is a number Trocheck has cleared or matched 7 times in his career. I'm not tossing shade on Bennett, but he's not on the same level as Trocheck.
I know AFP has generally been pretty accurate, but players like Bennett are the toughest to project because nasty players will generally get paid more than anyone thinks/predicts even if they're terrible players. Bennett is actually good so that number is going to start with a 7 at the very least especially after what looks to be another strong playoff run (unless he stays in Florida, he may give them a "discount.")
For the Rangers? I don't know that he really makes sense unless you're able to move one of Zibanejad or Panarin. Even then, I'm not sure where he fits into the lineup even if you do move one of those guys. He isn't taking one of the top 2 C spots and you could play him as a top 6 wing (he'd look good next to both Trocheck and Miller), but is that really the best allocation of those dollars/usage of this player?
I don't completely disagree with you but if we look at the 3 years prior to reaching UFA
Trochek
62 games - 38 p, 11g, 101 hits, 52.2% FO
47 games - 43 points, 17g, 107 hits, 56% FO
81 games, 51 points, 21g, 185 hits, 54.6% FO
Bennett
63 games, 40 points, 16g, 150 hits, 47% FO
69 games, 41 points, 20g, 173 hits, 45.5% FO
76 games, 51 points, 25g, 145 hits, 46.2% FO
Arguably, the 3-years leading up to UFA aren't THAT dissimilar.