Unlike Rafale, Mirage is tested plate form for IAF, they knew it strength/weakness & can make good tactics for roles in war scenario and have tested strong infrastructure. Indeed Rafale is better choice but for that Rafale needs atleast 5-10 year service in IAF.
Unlike Mirage, mki are more hungry for money. So until a new medium/light plteform doesnt come for service in IAF in # untill than older plateforms are good.
Cost of upgrade is too high, but we are seeing only a end not 2nd end. There is huge structural modification in airframe especially in change in wings and Avionics & architecture will be on next stage, on the of par of 5 gen fighters. Unlike mig29 where we only chose avionics modification.
Can you provide any links for that reddened part? AFAIK, there will be no structural modification, no airframe strengthening, or change to the engine. Only the electronics inside and the radar will be changed.
There will definitely be no change in the wings, which would make it a different fighter altogether, mandating years of flight tests.
Mig 29 upgrade includes new engines AND structural modification to increase internal fuel capacity (and clearly sports a new "hump"), not just avionics. It is the mirage upgrade that will have only avionics upgrade.