[Galorme]

The Lays of Belieriand (Book Three i think) is amazing. If, like me, you enjoy Tolkien's work in a more artistic way, rather than a set of academic texts, then the Lays, which includes The Lay of Leithian (Release from Bondage) and the Lay of the Children of Húrin, will appeal to you. While they add very little to what is said in the Narn and the Sil, it is great to hear the stories told in a poetic way.

And that is what most of the HoMe is, retelling the same stories from different perspectives and different ideas. You can tell what kind of reader you are by the books you liked best. I liked 9 for the Notion Club Papers, but a lot of people didn't like it as it didn't add anything to the mythology. I liked the Lost Tales as they tell detailed and beautiful stories, but a number of people didn't like them as they were so old the information they held was pretty much invalid.

Basically I could recommend all of the histories, but 6,7,8 and the first 3rd of 9 is entirely retelling the LoTRs in different ways and showing the development of the 2nd and 3rd ages, so read it only if you would be willing to re-read LoTRs.