Are you sure we can replace Zhuk AE with 2052 from Day 1? Then the jet has to be happy with Israeli Missiles of Derby/Python combo.. Russian missile integration will require customization with either a universal bus or a in between converter.. But yes thats a possibility no doubt..
The earlier 29s and 29Ks are different birds from Mig 35s..
The Mig-29M2 is a new family with a new airframe structure... the Mig-29K2 is based on it, as is the basic Mig-29M2, and the advanced Mig-35S. Just the same as in the 1980s the Mig-29M was a new build aircraft that the original Mig-29K was based upon too.
The original Mig-29 had a separate structure, with an outer skin. The fuel tanks were separate tanks placed inside the structure under the skin.
The Mig-29M used wielded outer skin panels so separate internal fuel tanks were no longer necessary... the separate sections were sealed off and could be used for fuel or components without extra layers needed, so it was much lighter structurally. The new Mig-29M2s are further developments of the Mig-29M, with the new airframe shape that was standard between the single and twin seater.
In terms of role and missions
IAF 29s are primarily an Air superiority platform whom IAF has prominently used as a second line of air dominance after Su30 MKI. Its also used for for Defensive Counter Air missions and Fighter escorts missions
MiG-35 but are more "role-specific" with pronounced qualities for Area Interdiction/Deep Air Support and Defensive Counter Air (DCA) missions. This implies a better A2G mission capability than Mig 29s of first point
If you are comparing it with say Rafale and pitting them as Rafale replacements then we have to understand Rafale is a very efficient multirole aircraft showing an high level of efficiency in almost any modern operational task and with very strong points in SEAD missions and area control. Its referred inside IAF more as TASA (Tactical Air Strike Aircraft).
Both Mig 35 and Rafale according to multiple experts show a very high level of survivability thanks to quality EW defensive suit, good low corner speed and enviable kinematical capabilities at transonic to mid-supersonic speed regimes.
Thus Mig35 will need new roles and will require new strategies and capability development.
Thats why its base of operations will be different from present infrastructure maintenance for 29s and so will be the weapons, munitions and its training+ maintenance..
Note:
As from Wikipedia
Air interdiction (AI), also known as deep air support (DAS), is the use of aircraft to attack tactical ground targets that are not in close proximity to friendly ground forces. It differs from close air support because it does not directly support ground operations and is not closely coordinated with ground units. Unlike strategic bombing, air interdiction is not meant as an independent air campaign, as its ultimate purpose is to aid ground operations rather than to defeat the enemy by air poweralone.
The purpose of air interdiction is to delay, disrupt, or destroy enemy forces or supplies en route to the battle area before they can engage friendly forces. Even at such degree, a distinction is often made between strategic and tactical interdiction; strategic operations are broad and long-term, while tactical operations are designed to affect events rapidly and in a localized area.
Air interdiction - Wikipedia, the free encyclopedia