If T.J. Mutcherson doesn't transfer/get kicked off the team, we could see the defense make a stride or two next year.
Our D-Line should be better. I know that's saying a lot with the loss of Morrissey, but like Blum mentioned we'll have Luna and Ayeni with 2 years of eligibility, Trent Taylor should continue coming into his own, Dale Pierson has been solid, Meyers, Aka, and Cousin are sophomores, Trent and Garcia are Freshman...the D Line in all of its watered down disgrace this year now has a considerable amount of experience and will continue to improve. Give Aka, Cousins, Trent, and Garcia another year to develop behind Meyers, Pierson, Taylor, Ayeni and Luna and I think D-Line will slowly become a strength of the defense like it was in years 1-4 of Rhoads. It will still be low-level Big 12 talent at best, but playing with a chip on their shoulder and all the experience in the world. This doesn't even include whatever new guys Rhoads is bringing in for the D-line
LB is a scary position IMO. Each year someone has stepped up in the absence of losing a great one (JG for Klein/Knott, Miller for JG etc.) but I'm not sure who fills Miller's shoes next year. Could be Jordan Harris, or we could see Alton Meeks finally come into his own (he is just a FR). LB our weakest position defensively next season IMO. Hopefully L. Knott can beef up a considerable amount w/o losing any speed. He is our best LB right now, but not much bigger than a safety unfortunately.
Overall I'll be optimistic. The offense should be improved and ready to roll in year 2 of Mangino. Returning most starters minus Farniok, Bibbs and Wimberly. Farniok will be missed the most out of that trio. Who replaces him is a question I don't have an answer to, hopefully Rhoads does. As good as Bibbs is/has been, I'm not convinced his departure is an extremely vital blow to the team. Others have mentioned that he isn't a great leader and maybe he did a lot of little things behind the scenes, but I never felt anything he did was game changing (aside from the diving catch to beat Iowa). Still hope he is able to make it into the NFL though, as it would be great for ISU. Playing here especially during the part of Rhoads tenure will probably really hurt his chances at being drafted high.