(We also meet the earliest version of Sauron, as Tivaldo the evil king of cats and servant of Melko, a counterpart to Beren's heroic dog.)
The other story treated in depth here is "Turambar and the Foalókë", which however has since been published in a pretty definitive format as The Children of Húrin; I found the joins between Beowulf, Kullervo and Tolkien's own imagination much more visible here.
The most interesting of the other chapters is "The Tale of Eärendel", another story which is curiously flat in The Silmarillion, a lost tale that underlies a fair bit of Middle Earth mythology but never seems to have found a definite written form; one almost senses Tolkien feeling more comfortable with it inside his head, so that Bilbo and Aragorn could make in-jokes about it in Rivendell, rather than spoiling it by putting too much down on paper.
(Also a shout out for "The Fall of Gondolin", with its gripping account of hand-to-hand combat as the city is taken.)
Despite the density of the prose I have found both Lost Tales volumes fairly quick reading, Tolkien's prose being as fluent in his twenties as it was later in his life, and Christopher Tolkien's annotations being complete enough to satisfy curiosity without being overwhelming. I'm glad to have got back into this series of books.
< Book of Lost Tales I ¦ Book of Lost Tales II