I've had mine in the tripple digets and never had a problem with the front end feeling light. I do move ahead on the seat when cornering to add weight to the front wheel. I'm guessing it is your set up. Many times it is the back end being too low. You can either add preload to the back shock or raise the front forks in the clamps.
I don't know what you mean by strung out on the hwy. I run 65-70 mph a lot and it just purrs. It is running in 4000 rpm range, which is lower than a lot of bikes.