I’ve read all of those (yes, even The Silmarillion). They’re the only high fantasy works I’ve read, so I’m not in a position to compare it to others in the genre. I’m not interested in the genre in general, but AFAIK these are unique in terms of the depth and breadth of world building that he sets them in. ~20,000 years of astoundingly detailed history of an area the size of Europe, a sumptuous attention to languages, and a whole cosmology laid out from the beginning of time.
The Silmarillion is for masochists only. I only read it because I was trapped somewhere once with no internet and nothing to do for a long time. A lot of it reads like the Old Testament (I think: hell if I’m ever going to pore through the Bible).
The work is racist and reactionary; divine rights of kings and such. From an ML-perspective it’s hot garbage. But whatever, it’s not like it’ll give you liberal cooties.