The MIG-35 is a very capable fighter. It is a more worthy investment compared to upgrading the old Mirage-2000s. I think the price for the upgrades is kinda inflated
Tried to post it yesterday, but the site still has problems from time to time, but let me give you some points just regarding the costs, which will make you understand that the Mig could never be a good alternative to this upgrade.
IN pays a system price of $46 millions per Mig 29K, that don't havs AESA radar, or TVC features and is more comparable to the Mig 29 SMT capabilities. The naval version is always a bit costlier than for the air force, so the latter should cost around $40 millions each. The Mig 35 instead, would come at least at $55 to 60 millions each fighter per unit, so no matter which version we take, the unit cost is not cheaper at all.
But there is even more, because the Mig is a twin engine fighter, while the Mirage 2000 is a single engine fighter and we all know that Russian engines are consuming more fuel, has a lower life and requires more maintenance than western counterparts, which translates into higher operational costs over the next 15 years (the time frame this upgrade is planed for).
We also know that the after sale support and especially the quality of spares for Mig fighters and the RD 33 engine is very problematic, which often results into higher costs as well, that's why IAF now even starts to look for western supplieres.
So all in all, although the Mirage upgrade looks expensive in paper (depends on what exactly we get in return), there is no real alternative for it, because buying new fighters is even more expensive, requires more time and except the case that we take the MMRCA winner, would add another type of fighter for up to 40 years to the IAF fleet.
All these are points that IAF don't want and why they insist on this upgrade, or why they prefered Mirage 2000-5 over Mig 29 SMT in the past, or EF and Rafale over Mig 35 today. Just like the air chief stated, a low unit cost alone is not imortant, but low life cycle costs, good quality of weapons and spares, good after sale support, or good future potential and as simple as it is, the Mig 35 can't offer these things!