The government owns the tooling, so it would be interesting to see what bids from Boeing, and Northrop Grumman would look like, in addition to LockMart's, to restart the line.
And the F-35's energy shortcomings are not all weight and power related. As pointed out in a separate thread, the F-105 could literally do everything better than a F-35 on less dry thrust (14,000 lbs) with equivalent thrust to weight ratios. The actual reason: the F-35 minimally conforms the Whitcomb area rule.