Pump up the tire pressures and take out some bar, front and back. That should give you better life. Maybe soften the rebound if they're still eating themselves. Definitely don't run any toe.
As for balance, make sure that the setup favors driving just under the limit. Back off the rear brake bias and soften the rear suspension. Use a loose diff setting for acceleration. You don't want to be on the limit for an enduro, just under it. Try not to adjust your driving, just make the setup do what you want. The setup that is favorable to the driver is favorable to the tires and anything else.
If you do none of these, then do one thing: a tall 6th gear. Hope that helps.