The bird is a half-assed project.. they should have left it earlier when the problems started to arise
And turned to what?
Its funny, I guess you had to be there, but people seem to forget the terrible problems we had with the F100 engines of the F15 when we were trying to get the thing certified for combat. For reasons we couldnt figure out at first, BTW in the middle of a monstrous Cold War, parts of the F100 engines were wearing out far faster then they were supposedly designed to do. It got so bad USAF was accepting airframes without engines to put in them and it didnt get straightened out until the early '80s. To this day we still have temperamental F100s on still flying F15s.
The F16 also inherited the problematic engine. But only one of them. It had severe electrical problems that caused the crash of several planes along with the deaths of several airmen. Its initial production run was about as basic a day fighter as we could make. Even in Gulf-1 most of the ords dropped by F16s were dumb bombs dropped at high Alts that totally missed their targets. It wasnt until after the Gulf War the 16 received Lantirn and AMRAMMS, "29 of 44 air kills in Gulf 1 were made by BVR missiles".
So I hope there are no delusions that any of these 4th gen aircraft had problem free development cycles. In fact they were far from it. The loss of life and airframes from WW2 and early jet development was horrendous.
There will be other hiccups in the F35 program. Just like in any other cutting edge fighter program, and if we had left them "when problems started to arise in the half-assed programs" we wouldnt be an air power at all.