Out of the 4 schools you mentioned, USF has the best foundation to take a hit and still pull through alright. Memphis is SUPPOSED to be pretty good this year though, so not sure if they are completely set back yet or not. Honestly, I hope they do well this season because that would be a testament to the (growing) strength/quality of the conference-which benefits all schools except perhaps Navy. Memphis probably won't feel the real hit until next season when the prior regime's workhorses have moved on. They might suck this year though, that's why the beginning of CFB season is so exciting-you never know what you really have. The relative strengths/weaknesses of the teams as a whole but our conference specifically are very fluid year to year.
To be fair, Strong should be able to pull in talent to restock the armory so to speak, but there is a better than 50/50 chance that there is a fall off next season and maybe season after that. I trust that he's become a better coach after dealing with what I imagine are very difficult conditions over at UT. With that, his ability to develop talent will be key. Rhule and Fuente found ways to develop relatively unheralded talent, that's the key to the mid term success of USF.