Rav Israel Salanter's idea of learning Musar has a few different kinds of benefits

The main motivation I had for learning Musar (=books of Erthics by the rishonim mediaeval authors) while at the Mir in NY was that I saw that people that emphasized fear of God in their own lives seemed to do a lot better in learning Gemara than those that did not. I.e. there were people that did not learn Musar were smart, but their logic often seemed "krum" or crummy. While people that emphasized Fear of God when it came to Talmud their logic always seemed a lot more straight.
[Then on the other hand I recall there was one fellow at the Mir that seemed to be getting too much into Musar and that certainly did not add to his learning nor fear of God.]

Some years and tears later I asked a fellow to get me the book of Isaac Blazer [the disciple of Rav Israel Salanter] The Light of Israel and I noticed right on the first page he makes a claim that Musar heals spiritual disease. That is he says there that just like the body has physical diseases so the soul also can get sick. And just like for physical disease one goes to a doctor so for a spiritual disease one must go to the doctors of souls which are the rishonim--the authors of the books of Ethics of the Middle Ages.

Another advantage of Musar is it is more philosophical true to Torah. It comes in a time period when people were thinking more rigorously about philosophical issues. [So you do not have circular logic which plagues most philosophers from the Enlightenment and onward. That is most Enlightenment philosophers assume what they set out to prove.

Hegel and Leonard Nelson

Hegel and Leonard Nelson have a difference concerning immediate non intuitive knowledge. The difference can be thought to be vast because in Hegel's system there does not seem to be room for awareness of values that do not seem dependent on reason or sensory perception.
For example--what is the difference between J.S. Bach and mere modern noise? With Kelley Ross and Leonard Nelson there is an answer. But in Hegel there is only pure reason and sense perception and their synthesis.
So to me it seems that each is important.
[In Poland there are people that think the argument between Leonard Nelson and the Neo Kantian people--Herman Cohen and others was overly exaggerated. But I would go further to suggest that even the difference between Nelson and Hegel are overdone.]
[Bezmenov in his video explains how communism infiltrated American universities but that does not seem to me to be the fault of Hegel.] Any system can be perverted. see https://stevedutch.net/pseudosc/10dumrel.htm

Christian writings

One theme that comes up in Christian writings is the Oral Law. I would like to mention that most things that are considered to be from the Torah in the Gemara have support from a verse. One early example I encountered was in Shar Yashuv [Rav Freifeld yeshiva in NY]. That year we were learning Yevamot and I saw how the issue of Yibum is treated very rigorously and derived from the verses. I also saw this in my first period in the Mir when we were learning Nedarim. In particular I recall the 11th chapter of Nedarim where the verses are analyzed in a very rigorous and logical fashion.
So legal issues --about what the Torah really requires is really a forte of the Gemara. And I see no good reason for Christians to disparage the Talmud.
 However there are other times in the Gemara that instead of open verses, the meaning of a text is derived by the 13 principles of derivation.  These rules-- most rishonim believe make things that comes from them to be considered from the Torah. However the Rambam thinks rules that come from the 13 principles of derivation can be overturned by a later court of law that is wiser and more numerous.

However it seem to me the main unconscious objection of Christians to the Oral Law is that there are a lot of rules. I can only wonder what they would say if they saw a NY code of Civil Law. Or if they ever would walk into the Harvard Law Library. --And they are accusing the Oral Law of having too many rules? That is rich!

The other theme that comes up is the idea of Jesus being God which certainly he did not hold from. However it is common in Moshe of Cordoba and Rav Isaac Luria to find people whose soul is from the world of Emanation [Azilut A-tzi-lut] which is considered to be Divine in the sense that there is no dividing curtain between Azilut and the Infinite One.

On the other hand there is a noticeable tendency to criticize belief in Jesus in any shape or form that goes beyond criticisms like these.It seems as if people are just searching for ways to criticize Jesus and anyone that believes he was good as a forgone conclusion.[I mean to say that they have come to their conclusion before weighing the evidence.]

Jesus I think would have been more accepted if not for the introduction of external doctrines which seem to interfere with his message

Jesus I think would have been more accepted if not for the introduction of external doctrines which seem to interfere with his message and do not seem to contribute anything on the positive side. For example bitul hamitzvot [nullification of the commandments] and the worship of him as is done seems to be doctrines that are just added baggage and tend to rake away the value of his message.
The actual message I assume is more or less contained in things that he said instead of things said about him. There are lots of examples of this. One case would be the Sermon on the Mount. That seems to be meant literally even though there do not seem to be many people that think that Jesus was actually serious about the rules he was prescribing there.
However, I believe that the Amish and Mennonites actually do take the rules of Jesus seriously. I think that is what distinguished the Anabaptist.

It is tragic that the only places in Israel that follow the path of the Gra and Rav Shach are the yeshivas of Rav Zilverman in Jerusalem and Ponovitch and Brisk.

The importance of the Litvak Yeshiva path is mainly in a closed community that is based on Torah. It is not really meant as a way of government. So as far as government goes I am on board with John Locke and the  Constitution. of the USA And the Constitution itself recognized the difference between state government and federal government. But on the level of small communities I see Torah in the way of the Gra and Rav Shach as being the ideal to strive for.

I ought to mention for the sake of clarity that somehow or other through my experience in Shar Yashuv and the Mir in NY that when I got to Israel I underwent a spiritual transformation. So I am convinced by reason but also by personal experience in the validity of the straight Torah path advocated by the Gra. 

It is tragic that the only places in Israel that follow the path of the Gra and Rav Shach are the yeshivas of Rav Zilverman in Jerusalem and Ponovitch and Brisk.

I found the contribution of Dr Kelley Ross of the Kant Friesian School to be quite amazing.

I found the contribution of Dr Kelley Ross of the Kant Friesian School to be quite amazing. The major points are immediate non intuitive knowledge and a polynomic theory of value. The reason this helps is that there seems to be areas of value that are not reducible to true of false. Sometimes the question is J.S. Bach as opposed to noise. And even in areas of true of false you have to start with axioms that are immediately clear-but can not be reduced to prior axioms.

Still the argument of this side of Kant with Hegel seems a bit a bit overdone. There seems to be a lot more in common between Hegel and Leonard Nelson than there are differences.

In any case, what is important about Kelley Ross is that in his system there is this kind of knowledge that would be called faith. But then comes the question how to distinguish between true faith and false?

My feeling about this is that any bit of true knowledge has to come from a component of immediate non intuitive knowledge and also a component of pure reason. But that does not make it infallible. If Empirical evidence goes against it, it has to be modified of maybe even thrown out.

Communism based on the idea that man in state of nature is good.

while Michael Huemer is right that Communism is based largely on the labor theory of value it also has an implicit foundation in the state of nature of Rousseau  that man in the state of nature is good. All theft and murder and all other human evils come from society. But if you would put back man in the state of nature everyone would be loving and kind and cooperative. (It is just the exploiters that extra value from the workers that would have to be gone.) No need for government or rules. But Marx admitted the tremendous abundance that capitalism creates. So he postulates next stage of evolution where the means of production will stay put, but the exploiting class will disappear, and people will revert to their natural loving kind state --but along with that there will be no government nor society and no inequality so  no reason for theft or violence.
[Marx did not usually say from where his ideas came from, but in one comment he acknowledged he was influenced by Rousseau. But it is more than that. He claimed his ideas were scientific. The idea was to create a science of man that would be on the same level as Newtons science of gravity and motion.]

So Allan Bloom [The Closing of the American Mind] is right for tracing the  crisis of Western World as being rooted in the question about what is man in the state of nature.]