How about an F/A-18 derivative, but with a diamond wing and canards? I have a feeling I've seen a picture of such a design, and it looked pretty good. A joint project to replace F/A-18s, F-16s, Tornadoes, Mirages etc, as a canard delta enlarged F/A-18, but perhaps with a pair of F-110 engines, would be good. With some stealthy features added, but without going all out for stealth, it could have been a good alternative to the JSF project. The aircraft would borrow some design touches from the F-22, but mostly using RAM coatings and better general design features. The aircraft would be licensed for production to multiple countries, with everyone having the choice of engines, radars etc, but with a common basic airframe. The French could build it using a much more advanced M-53 or larger M-88 engine, and French radar. The UK could use a RR engine (enlarged EJ200, preferably around 20k lb dry and 28k lb with reheat), and a British radar. The Aussies could use American engines, and radar, or perhaps an Israeli radar.
Basically, it would be a genuine JSF, with each country buying a license for a set number of aircraft, paying for a bare fuselage, so anyone can export them. Each country thus pays a basic license fee to build an airframe, then fits their own avionics and systems, and then can export them if they want. France, the UK, possibly Israel might all want the option of offering their own versions to others, and would be permitted by virtue of paying for the original development.
Total orders:
USAF - 2000 (replacing F-16s, and some F-15s)
USN - 1500 (replacing F-14s and F/A-18s)
USMC - 500 (replacing their Hornets, and possibly their Harriers too)
RAF - 450 (replacing Tornado F-3s, GR-1/4s, Jaguars etc)
RN - 150 (to equip the new carriers)
AdlA - 450 (replacing all the Mirage 2000s and F-1s)
MN - 150 (replacing Crusaders and Etendards)
Luftwaffe - 200 (replacing Phantoms and Tornado)
Italian AF - 200 (replacing Starfighter, Tornado, and ultimately AMX)
Spanish AF - 200 (replacing Hornets and F-1s)
Israeli AF - 200 (replacing A-4s, F-4s, early F-16s, etc)
Turkish AF - 200 (replacing F-4s and F-5s, and eventually F-16s)
RCAF - 100 (replacing Hornets)
RAAF - 100 (replacing Hornets and partially replacing F-111s)
Danish AF - 50 (replacing F-16s)
Dutch AF - 150 (replacing F-16s)
RNorAF - 100 (replacing F-16s)
Greek AF - 200 (replacing F-4s, F-16s and Mirages)
Egyptian AF - 100 (replacing various types)
UAEAF - 100
South Korea - 100 (replacing various types)
Singapore - 100 (replacing various types)
There are probably more, but even just the ones listed would amount to a staggering 7300 aircraft!!! Okay, some of the figures are optimistic, but if the aircraft were a simple good performer, basically combining some of the stealth features of the F-22 or F-35, but with a basic airframe like the Hornet or Typhoon/Rafale. This all depends on it being built in the '90s in place of the other aircraft of course, but if it had happened, that is a massive total!