"How can Brockers, who is definitely a good to very decent DT only a reasonable contract once traded, a great leader/team mate and no real injuries only get a 7th rounder in the distant future...."
It's because of the cap.
Brockers would have counted $8.83M against the cap and his trade was all about cap relief. By trading him, the Rams got $6.17M in cap relief in addition to that 7th round pick.
The Rams could have cut him, but they would have had to pay him the $1.5M that was still guaranteed on his contract, and that would have reduced his cap savings to $4.67M. By trading him rather than cutting him that obligation went to the Lions and the Rams got an additional $1.5M in cap relief plus that draft pick.
Michel 'only' adds $555,747 to the Rams cap, making him a more attractive acquisition and therefore raising his price.
AlbaNY_Ram