I'll listen to the cover soon, but I will say that Buckley was a vastly underrated songwriter (still is), and even more underrated as a guitarist. His voice is undeniably great, but his real talent is in songwriting and I'd hope people realize that after the initial draw of his voice like you said.
Oh I definitely agree. "Dream Brother" is probably my favorite off "Grace." "Lover You Should've Come Over," and "Everybody Here Wants You," are brilliantly well written. I just think people notice the songs a lot less than they notice his voice.
It's (I think) a general conflict with great singers: Sometimes they sing so well you don't really hear the words. It's why I think word-heavy/complex storytelling lyricism really succeeds (not necessarily in my opinion, just in terms of records sales and critical acclaim) with simpler melodic vocal approaches (Paul Simon, Tom Waits, Bob Dylan, all hip-hop) and really acrobatic vocal performance seems to warrant really simple lyrics (Luther Vandross, Donny Hathaway, Anita Baker, most soul music).
Good call on the guitar. You into that Sin-e EP? His playing on that is awesome.