First, as you argue, they've been awful not because of their top talent stinking but rather, because their bottom talent has been significantly below average over significant amounts of playing time.
Second, they aren't likely to be consistent contenders because while their top talent is good, they really have yet to collect "uber-good" with really Bruce being the only "uber" candidate they currently have.
So really, Jocketty's job is more than simply setting the floor at roughly league average (i.e. burn up the chaff)-though that would be a leap in improvement, but he's also got to add a second story onto the house.
It's a tough job.