If I had to guess the problem they have, I would imagine they would like a proven head coach to take over their program. Jimbo will not be as exciting of a hire as they'd like, and if FSU doesn't start winning championships again, I doubt they will want him at all when Bowden steps down.
No head coaching experience. The only impressive thing on Jimbo's resume was that he was OC of LSU from 2000 to 2006 and OC of FSU since then. FSU's offense is pretty good this year, but it was weak last year. Also, it smells of nepotism when you consider that Jimbo is an old friend of the Bowden family. His connection with Terry Bowden: Jimbo played QB for Terry when Terry was head coach of Salem. When Terry left to become head coach of Samford, Jimbo transferred with him. Then Terry hired Jimbo as his OC at Samford. When Terry left to become head coach of Auburn, Jimbo followed him to Auburn, where Jimbo served as his QB coach. His connection with Tommy Bowden: Jimbo was the QB coach for Tommy Bowden when Tommy was the OC at Auburn. His connection with Jeff Bowden: Jimbo played QB for Jeff when Jeff was the OC at Salem and when Jeff was the OC at Samford. When Jimbo became the OC at Samford, he took Jeff's spot. When Jimbo became the OC at Florida State, he again took Jeff's spot.