Sir,
the problem is real combat is not a video game. Every fighter plane takes off with a specific mission. Its not like a "Sultan Raahi" or "Rajni Kaant" mission, where you will have to engage each and every one. Carry everything with you from Needle to Pen, remain in air inside enemy territory until your fuel gauge starts beeping and you are not left even with 1 bullet.
The only advantage (and thats a big one) IAF has with long range fighters is that, they can place them deep inside India. Coupled with their natural geography, it will place their aircrafts well away from PAF strikes. IAF learned this lesson from 1965 War. In 1971, PAF has only Runways of IAF's FABs to bomb for. Unlike, 1965 there were no aircrafts neatly lined up on bases within reach of PAF fighters. An MKI can fly off from even from Southern India all armed to strike inside Pakistan. They dont need to keep it on Halwara or Adampur, which are hardly 200Kms away from PAF bases.
Other then that it will not be circling around Pakistan for 5 hours. It will drop its bombs, whatever its mission is and leave as early as possible, without waiting for challenge. When its on Air Superiority mission, it will surely wait for some A vs B engagement.
Pilots are human first. They have their physical limits. In situation of war, can you imagine, how much stress is there on pilot? Even after 1 hour mission, he will be physically and mentally challenged to the limits. Here you have 2 pilots. After 5 hours mission, can they fly again for other 24 hours?
Answer is NO.
Kindly also check, Thunder proposed configuration, for various roles.
On every mission, some will be covering the asses, some will be striking..
Rarely, it will be a SOLO flight.
Will love to discuss with you more over it. I think I will learn more out of it. For your interest, check out below article from an IAF officer about medical aspect of long duration flights.
Regards,
http://medind.nic.in/iab/t05/i2/iabt05i2p41.pdf