Eep - the recovery time rule will make a major change to the way things work out.
One thing I'm worried about is where someone gets taken negative (like happened in the last fight), and then no matter what we do to heal them, a single magic missile spell at CL 9, or a fireball, or whatever, will always deal enough to take them from 0 to -10.
Possible alternative suggestion - during the recovery time, a creature counts as staggered, despite hit points being higher than 0, and strenuous actions will either a/ cause a point of blood loss, or b/ drop the character to -1 and bleeding?