For me, Williamson already has his nose in front & of course will go on to be have a miles better record by the time their respective careers have finished.
Totally different batsmen btw,
Ross is very much a hand-eye player who generally needs a decent amount of luck to survive early on due to uncertain foot work (at the start of his innings) & his propensity to push & prod with hard hands, but once in, he can obviously be devastating.
Kane on the other hand is a proper old fashioned classical Test batsman - one of the few going around who rarely looks in trouble even at the start of his innings. About the only weakness he has (which is actually also his strength), is sometimes playing through the off-side a little early in his innings. But, generally his feet are moving beautifully from ball 1, which is rarely the case with Ross.
I'd take Kane to bat for my life any day of the week over Ross these days. I would not have said this in 2013, but wouldn't even think twice about it now.
To those suggesting Taylor may be unmotivated by Kane's success, I very much doubt that would be the case & would be massively disappointed if he really was that petty and envious of a team-mate, I think instead he's as excited & delighted about Kane as we all are.