Actually, on condition of fielding a few mods like putting the PAK-FA IRST on it, a transparent gold leaf on canopy to close the Faraday cage and well, not sure if the anti-bird cache in front of engine fans can avoid radar reflections here, maybe adding a few sawtooth surfaces on some areas, make sure you fit Khibiny pod then...
Mig-35/29K shouldn't have too much problems to eat F-35, F-22, J-20 and J-31. If a powerful L-band radar is added in a pod.
Mig-35/29K with very few mods would be my 2nd choice after Rafale to build an air-force as it's also built from baked-in RAMs, also uses exhaust cooling and also has active stealth available. It's clearly coarser and less refined than Rafale but there is very serious potential.
I don't think PAK-FA will be built in huge number, it's more to be seen as a replacement to Mig-31BM, doing ani-stealth/AEW job + sniper job and also sneaking into aggressor lines to attack high value assets (AWACS, refuellers, JSTARS, ELINT, MarPat, cargos and also CV/CVNs, destroyers, etc).
Actually, what would be REALLY devastating would be a F-35 shot down by a... Yak-130! And the funniest thing is that, if equipped with what it takes to do so, it's absolutely feasible!