????? F-22 is stealthy, no? Sounds like the F-35 was just a play thing for bilking the gov't of money.
As I understand it the F-22’s electronics architecture is really somewhat limited. What they need to do is build a new Block that entirely starts over while preserving the airframe, engines and as much of the avionics as they can. Incorporate the Helmet cueing system and so forth. BTW that is still a very tall order. And it will very much be a new aircraft — a Super Raptor.