This is my take on both sides of the ball. I think the defense could see a huge turnaround next year if Mertens gets another season. The offense will depend on the development of the offensive line.
Defense
Mertens getting a sixth year would be huge for the defense. That would fill the biggest hole on the defense and allow the other guys like Diamanti, Boyland, Appleby, and Fields to be depth and develop another year.
Yarbrough and Puletasi are clearly the starters and left and right end but the depth seems like it may be thin. Riley Lange could provide depth if he isn't moved to the offensive side of the ball. I think Jordan Stanton would fit better at end in the Tampa 2 scheme and Hala'api'api could also provide depth here.
I like Nzeocha's athleticism at weak side linebacker and Wacha at middle linebacker. I don't think Jordan Stanton is fast enough for the Tampa 2 so I would go with Hala'api'api or Harris(if he gets another year) at strongside linebacker. There are a lot of linebackers on the roster so the competition should be fun to follow. Nzeocha is the only guy I feel is a lock to start.
Burns, Hayes, Finley, and DeAndre Jones would battle for the 1-4 corner spots, Xavier Lewis will start at strong safety, and the free safety spot will be a battle with Jesse Sampson probably starting at the top of the depth chart.
Offense
It's too early to tell who the quarterback will be but I'm going to assume Aaron Young has the lead right now. I don't think Tommy Thornton has the arm strength to be a DI quarterback and Austin Fort needs at least 1 year and probably 2 or 3 to develop his mechanics as a passer. It's scary to say but right now, Chris Little(see new QB? thread) would be the biggest competition to Aaron Young if he comes to Wyoming.
Wick is clearly the #1 running back but I think the freshman from last year could get into the rotation and D.J. May could come off his injury to provide some depth. I like the idea of experimenting with Jordan Stanton at fullback due to his size and physical nature. I think he's too slow to be a Tampa 2 linebacker. There are a couple other defensive guys who they should experiment with at fullback like Hala'api'api, Dan Crook, Riley Lange, and J.J. Quinlan if he gets another year of eligibility.
Tight end will be interesting to follow. J.D. Krill was a dud for D.C. but he has great size. Hopefully he can be at least a capable blocker. Jake Maulhardt is a big receiver who would need to put on a lot of weight to play tight end. He could be a possibility but probably needs more than one year to gain the necessary size. Jacob Hollister is an interesting JC player who has a good chance of starting next year. After that, there are a lot of defensive guys who could possibly make the switch, listed above with the fullbacks.
Hopefully Tanner Gentry doesn't transfer because he is going to be a special player. He and Rufran should be starting next year with a ton of guys competing for playing time behind them.
The offensive line is a toss up right now. Bohl needs five guys to work their asses off this off-season and prove they deserve to start. He needs to start changing their mentality from day 1. The development of this group will likely have the biggest impact on the success of Wyoming next year.