Talent wise, Taylor obviously has more basketball talent than Cato. But Cato is more valuable to Rockets under JVG system because of his tremendous defense presense. Our defense really go down a notch when he did not get the minutes. As talented as Taylor is in the offense end, he offensive skill cannot compensate his deficiency on the denfend end (Especially his rebounding skill). So I think Rockets would like to trade Taylor before they trade Cato. The reason that most trade talk is involved in Cato instead of Taylor is most teams in the league does not need a VASTLY overpaid one demension PF while most would love to have a defense minded rebounder and shot blocker in the middle, even he is little bit overpaid.
