persistence cookie at BIG IP level too persistent?

To provide an example of rappy's solution a) above, simply try adding this to a rule on your virtual:

when LB_FAILED {
   if { not [info exists retry_count] } {
      set retry_count 0
   }
   if { $retry_count < 3 } {
      LB::reselect
      incr retry_count
   }
}

For solution b) you'll have to wait until 9.2 ships as it requires some new commands that are only available in 9.2.