I differ a little in my guess for "roles"
Toia battles with Rodgers for the last DL position (only 4 making the 53). They will only keep one, and Mazi isn't due a new contract yet and was drafted to high to admit bust "yet". Osa and SThomas have the 3T for this year, Mazi has the starting 1T......so Rodgers or Toia are the last DL spot this year. They will keep 6 DE's barring trade.
Tommy Akingbesote is really a bigger 3T, and not a 1T. Best guess he was drafted to go to the practice squad, and take Solomon Thomas position next year when he wants a new higher paying contract.
Rbs will most likely be on the team, IF, Mafah proves to be the best power back. I could see them basically cutting the existing ones and having a new backfield next year. This one will be a battle, and depend on how the OC wants to utilize backs.
DonoEz is in the rotation with the other 5 guys. They keep 6 DE and 4 DL.
Shavon they are hoping will allow them to cut Diggs next year or not have to pay Bland. Win, Win for Dallas if he plays out.
Ajani Cornelius is practice squad all the way. Swing tackle or can take either if he develops. They don't need inside help presently.
Shemar James, imo, was drafted to back up Overshown, and play special teams. Development guy who may end up on practice squad IF someone else stands out, if not, then plays behind Overshown.