Wide Receivers (5)
Amon-Ra St. Brown
Jameson Williams
Kalif Raymond
Donovan Peoples-Jones
Isaiah Williams
After they did not draft one, wide receiver feels ripe for a post-draft free agent addition for the Lions. Williams is an undrafted rookie who was given a significant chunk of guaranteed money to convey the chance he's in line to get, an I think he earns a roster spot.
Tight Ends (4)
Sam LaPorta
Brock Wright
Shane Zylstra
James Mitchell
LaPorta and Wright are the obvious top two here. Zylstra may have made the roster last year if not for a torn ACL in training camp. Mitchell's latent potential keeps him around one more year, even if he doesn't have a clear path to a bigger role.
Offensive Line (8)
Penei Sewell
Taylor Decker
Frank Ragnow
Graham Glasgow
Kevin Zeitler
Christian Mahogany
Colby Sorsdal
Giovanni Manu
The top six here are easy, the five starters plus the rookie draft steal Mahogany. The trade to get Manu with a top-130 pick in the draft assures him a spot, for better or worse as he makes the jump from the University of British Columbia to the NFL, and I've got Sorsdal sticking around over Kayode Awosika. The Lions did sign three undrafted rookies who are interior offensive lineman, with notable financial investments in two of them, and perhaps one of them ultimately wins a spot on the active roster.