Larry Asante-S-Nebraska—Notice I didn't give Asante the SS or FS title. This ability to play either position makes him a hot commodity in Jim Schwartz's defense, as he likes players who have that capability. Asante was a very underrated part of the Cornhusker's highly-touted defense this year.
AJ Edds-OLB-Iowa—Another solid player from a school with a very good pedigree for breeding linebackers. A very smart, tough player, Edds would be another option should the Lions find themselves short at linebacker.
Syd'Quan Thompson-CB-California—Thompson could drop if he doesn't run a good 40 time at the combine. However, it's hard to knock his production and the fact that he never missed a game in his four years of starting. He also has some punt return skills.
Vladimir Ducasse-OL-UMASS—Level of competition will be an issue, but Ducasse has a lot of potential. He is a large road-grading type of offensive lineman that even the Dallas Cowboys would have trouble scoffing at. He might take a year or two to develop but could help solve the Lions trouble at guard down the road.
NOTE: While I would prefer to see a WR be a priority in Free Agency, I cannot say for sure one won't be targeted in the draft, so to be thorough I will include a few of them.
Mardy Gilyard-WR-Cincinnati—Gilyard was ridiculously productive at UC and is the kind of deep threat that could help take some heat off of Calvin Johnson. However, think of him like a poor man's Randy Moss as he might have trouble running routes that aren't fades and doesn't nearly have the size Moss does. Gilyard is, however, a very good return man.
Jacoby Ford-WR-Clemson—One of my personal favorite players on the North side, Ford has the speed to be a DeSean Jackson type player at the next level. His production was somewhat limited this season with Clemson's offense struggling, but his 40 time alone will get him drafted in the third round. He is another player with incredible return skills.