In the a2a domain, they rather obviously aren't.
Rafale is an interesting and unusual (asymmetric) a2a aircraft, but because of that it always struggled to be around the 'strongest' title even among peers. Now its peer era is long gone.
Overall, your claim may have merit, because Rafale is a fully developed, all-purpose aircraft with mature capabilities everywhere; literally, the single hole in its capabilities is the lack of ARM. But for specific applications, it isn't best...probably nowhere.
If measured as omnirole and when its lack of LO isn't decisive, Rafale is indeed probably the most capable aircraft on the market right now.
Yes, more capable than current F-35.
The substantial cost per Rafale mostly means that you're supporting small rate of fully domestic production of a developed economy(with per capita GDP 20 times yours) out of your pocket, and don't even get TOT for that. The fact that the Indian economy - a rather poor developing economy, - is being openly bullied, it is nothing to be proud of.
But that's the price of buying something from a politically powerful country that isn't US or Russia.