I would rate ROTS third. TFA is good action-wise, but it’s a remake of ANH. ROTS is original — it’s the most original subsequent film after ESB.
As a remake, TFA is very good. In many ways it’s better than ANH — which in all honesty is quite slow moving and can get a little boring. TFA is more entertaining as a pure action movie.
But it reuses so many elements of the initial trilogy (why have a droid land on a desert planet? even just landing on a snow planet would be a bit more original!). ROTS is the only film that has a story of descent into evil, and mostly does it very well.