NATO v equally equipped opponent

In another thread it was discussed how 1980s vintage Polish MiG-29s managed reasonable results against 2000s vintage F-16Cs in BVR and WVR. Only time F-16s did well was when supported by AWACS.

So let’s extrapolate a scenario.

NATO is going up against an opponent with similar levels of training, EW/ELINT support.

The key difference is in type of tech base – NATO is Western and the opponent is Russian/Chinese.

NATO’s key advantage is numerical superiority (thanks to USA).

Opponent’s key advantage is local terrain (say NATO is attacker as is more probable).

How would NATO fair against such an opponent?
– Would air superiority be attained
– Would NATO air forces be able to accomplish key missions.
– Would NATO air forces suffer unsustainable losses?

A second scenario
– Opponent is reasonably well trained (say 75% of NATO capability)
– Opponent is well motivated and has a functional integrated air defence system. Systems range from modern ala S300 to modernised older systems ala SA-2/-3/-6. Radar coverage is similar.
– Some EW capability.
– Opponent’s air force is also a mixture of modern (Su-30MK, MiG-29) and older (MiG-21, MiG-23, F-7M).
– Opponent has some offensive capability ala Su-24 and SCUD and is willing to use it PROACTIVELY.

– Basically we’re thinking Iraq 1991 but with better training, better planning and coordination, good morale as well as some technology upgrades.

How would NATO fair in scenario 2?