GE delivered what 6 engines out of 99 in 5 years, US stuff is tainted unreliable due to geopolitical reasons. They will have to partner with SK, or go all Russian for now and swallow the Rafale pill of no source codes.
Even if currently there might be parity Pak still needs J35s regardless. I dont see any point waiting for political reasons, im sure ultimately will come down to budget and maturity of the jet.
It is an interesting state of affairs, where India has all the money in the world, but hard choices on which jets to buy, and Pakistan has all the choice it needs, but no money to buy them with!
They will double down on Rafales, and convinced themselves it can be competitive against the F-35AE and J-10CE combo somehow.
India would do well to collaborate on the Su-75 Checkmate, with a
full Indian avionics and EW fleet for the Indian version(Indians can do software better than the Russians now as they have a far larger talent pool to draw from and better private companies in that space), and let Russia work out all the issues of the FBW, Engines and airframe design. Right now, that is the best decision(imho) as the platform has a better stealth profile than the Su-57 has.
The J-35AE will still beat any Su-57/75 combo of India, until India can get its own datalinks in place, and its own version of multi-domain operations which itself will take a decade.
The whole of the PAF with its datalink, multi-domain operations is now fully ready to absorb and operate a stealth fighter, and that is the product of sensible long term forward looking strategic military planning... Indians are having to reverse engineer all this now, and it will be at greate cost.