Serrano, I have no idea about baseball expectations. I would assume a "hold" there because of ...
Warlick, it's seems pretty obvious that she is not able to coach-up players to perform even at their talent-level, much less exceed them. This is the biggest replacement need atm. But, I don't understand the "emotional / political / honor Pat" influence enough to know if it can be done or not. That component may keep her around for another 1-2 years until we fully collapse.
Barnes, I think is safe for 2 more. The guy looks like the "on-court" opposite of Warlick to me. He knows what he's doing in prep and game time. His recruiting needs some serious mojo. But, if not, he's a stable force to at least placehold for a replacement who can get us to the next level.
Jones, he's safe after 2017, unless he lays a 7-5 egg IMO. Then the AD may have his hand forced. 8-4 puts him legitimately on the 18' hot seat, and anything more keeps him off it IMO. His buyout and collateral from "brick by brick" have earned him enough staying power.
IMHO, I would list the risks in this order 1.WBB 2.Baseball 3.FB 4.BB.