Kelley Ross as a philosopher has a thoroughness that surprised me. I had been aware of problems in Torah for a long while. One major problem was: "The difference has to make  a difference." If this one system is true and holy, and everything else is completely false and evil, then that ought to be seen in the traits and nature of people following the true system. If good and evil are simply divided along the normal bell curve, then that is a question. There were personal reasons also. I had encountered enough evil in many religious  people, and their leaders in particular, to raise doubts.
There were also intellectual questions, but these did not seem as serious as the others.
It was right at that time I discovered Kelley Ross's essay on Spinoza. 
That was a shock when I saw the depth. I never saw a modern writer on philosophy come anywhere near it.
But then I saw his major four essays on value, and that was enough to answer all my questions.
[There are other very good philosophers nowadays, but none that get anywhere near Kelley Ross.]
The only thing that bothers me is that he does not seem to have much of  a liking for Hegel.
That never bothered me as long as I never really read Hegel. [I did a drop in NY, but I did not know then what Hegel was talking about. Later with a little more background, I could read Hegel, and see what he was getting at,- and then I started to realize he has a lot that is really amazing ideas. ]
In a nutshell, Kelley Ross is a continuation of Plato, and Hegel is a continuation and deepening of Aristotle.

Even very good philosophers like Edward Feser and Michael Huemer tend to have a certain weakness when it comes to Physics. And that makes a lot of difference.

The most simple way to justify Torah in two words is objective morality. Moral principles are universals that can be known by reason. The Torah simply reveals what objective morality is. It does not claim to make people moral. And Objective Morality has a lot to do with midot (-character). Though it goes into areas of service of God also. But the starting point is midot (-character). If people have bad midot/character, that is a question on them and on human nature. not on Torah.