I haven't gotten to 琵琶行 yet -- one day, assuming I finish 唐诗三百首. I've been told it's more often taught in school than 長恨歌 because it's easier to read, rather than a better poem. :shrug:

FWIW, the index for all my translations is here, including an exceedingly rough rendering of a third of 道德经. A foundation of Daoist stuff does indeed help xianxia make more sense, at least its surface tropes.