Biggest needs IMO:
RB. Biggest need. Losing Kamara and probably Hurd. That's a lot to replace, but these kids should see an opportunity to come in and contribute immediately. Should be in good position to bring in some elite talent.
DE. We could lose A LOT here, if Barnett and Kongbo both jump. Vereen, Mixon and Lewis are gone regardless if I'm not mistaken. The good thing is that we have some very talented players waiting their turn - Phillips, Taylor, and Smith all have excellent potential. Still, need to restock the cupboard - maybe even look at another JUCO DE if Barnett and Kongbo both look likely to go pro.
Interior OL. I believe all of our '16 OL commits project to OT, which means we effectively didn't take any interior offensive linemen in this class. Need to make up for that in '17 - Thomas and Robertson both likely have two years left but this isn't a position where you want to rely on freshmen... get some premium talent in and let them do work on the practice field and in the weight room before they have to face the fire.
DT. We aren't in immediate danger here, with only O'Brien slated to leave after next season. The potential problem is the year after that. Johnson and Vickers are gone, and both Tuttle and Kahlil become draft-eligible - and have the talent to bounce. Need to prepare for that now - would love to get a couple of elite guys ready to carry the torch starting in 2018.
TE. Croom is gone, and Ethan Wolf has the talent to jump after his junior year. That could leave us with a lot of potential uncertainty - Creamer and J. Johnson have yet to prove that they deserve snaps. IMO Pope is a sleeper candidate coming in, but he hasn't earned anything yet. Brooks has the most natural talent of the three but needs to get healthy. Not an immediate concern here, but a situation that merits watching - if Wolf jumps and none of the young guys step up, we could have a hole here.
LB. This is low on the list because I believe we already have the pieces here... just need them to develop. McDowell, Bates, El. Berry, Bryant, Sapp, and the incoming freshmen all have tools. Like TE, LB only becomes a problem if several of these players fail to develop as anticipated.