We should have had 250 Mirage 2000
And 250 MiG 29s
If you have one, the other is pretty much redundant.
A far better option would have been if we had procured ~200 Mirage-2Ks in the 80s and 90s (with HAL production), followed by ~200+ Su-30MKIs in the 00s and 10s. The upgrade process to bring the Mirages upto the 2K-5 standard should have begun in the early 2000s itself...and then Rafales should have started coming in 20s.
The MiG-29 was a totally unnecessary addition to the fleet which would never have been bought if it wasn't for political dealings between Indira Gandhi and USSR.
Would like the Su 30 upgrade done indigenous ly.. How small the increment is..
Need to integrate our own radar with source code.. And buy better missiles from any source. Preferably our own.
Idea is to spend less in upgrade just adequate enough for the threats.. And spend more on getting more platforms.
Do we need to upgrade to new engines?
Is the current engine underpowered or cannot be powered up by other means ?
The MKI upgrade hinges on few very important things:
a) the radar - without an AESA upgrade, the Su-30 would not stay very relevant into the 2020s and 30s with the perceived enemies deploying LO/VLO aircraft equipped with AESA antennas of their own. The existing Bars PESA will not maintain its ability to look first & shoot first against these emerging threats.
Whether Russians allow us to install a potential upscaled variant of UTTAM is doubtful. If they don't, we effectively only have 2 choices - either waiting for Tikhomirov to come up with an AESA antenna for the Irbis-E radar, or just go with the PESA Irbis as it exists on the Su-35S.
b) the engines - the existing AL-31FPs, like most Russian engines of this generation are extremely maintenance intensive compared to the Western F404s, F414s and M88s. Too many man hours & money is wasted keeping them in top shape. An upgrade to an engine with better TBO & MTBF figures makes sense, not to mention the increased power needs of the new avionics plus the possibility that the jet could get heavier after all these additions like MAWS etc.
the AL-41F1-S i believe is the engine in consideration a.k.a NPO Saturn 117S. same engines as on the Su-35. These engines are ready and in production so there's nothing on that front slowing the program down, someone correct me if I'm wrong.
to ask your question "do we need to upgrade engines" I'd say if we're not going to upgrade them, the scope of upgrades we might do on the rest of the plane might get somewhat limited. And I always advocate doing all necessary upgrades at once instead of doing some things now and others a few years down the line, things are just more efficient that way (doing everything at once).
c) survivability - the MKI lacks both a set of Missile approach warning sensors (MAWS) as well as an internal Self-protection jammer (SPJ), latter of which necessitates the allocation of a wing hardpoint to carry the external ELL-8222 jammer. These are both must-have pieces of equipment for any modern air-to-air combat aircraft. And if you ask me these are THE most important upgrade MKI needs.
DARE has decided a pursue an indigenous MAWS solution although a far simpler approach (which wouldn't need much re-testing & airworthiness certification) would have been to adopt the SAAB IDAS suite which is already used on the Malaysian Su-30MKM (as well as various Indian platforms like Dhruv, Rudra, LCH etc.)
I have no idea what internal SPJ is being pursued - or if any is being pursued or not.