Many people are aware that the published Silmarillion was compiled by J. R. R. Tolkien’s son Christopher, with an eye towards consistency and concision at the expense of poetic detail, from a wide-ranging variety of incomplete (and often mutually contradictory) manuscripts left by JRRT. I have read some volumes (not all) of the History of Middle Earth, which includes many of the source texts Christopher Tolkien used, but I have only recently become aware of the third-party scholarship showing how it all came together, in books like Arda Reconstructed. Also interesting are the fan attempts to construct more comprehensive and poetic-sounding Silmarillions than the one published by Tolkien’s son. These can seem a little dry, because for copyright reasons, they are basically citations to texts compiled in the History of Middle Earth.
This one is a “finished” one-fan project: http://tasarinan.atwebpages.com/silmap.html
This one, the work of many hands, has been ongoing for twenty years: https://forum.barrowdowns.com/forumdisplay.php?f=16