...I was told that Cherubim meant "Shining Ones" while Seraphim meant "Burning
Ones"; the suggestion was that the light of the Seraph was more intense.
The Jewish Sages WE consulted never said anything about snakes. I think
(WARNING: I'm not a Rabbi & don't speak Hebrew) that whatever the origion
of the word it lost it's mythological connection in being applied to
Angels.
But in any case we are talking about WAY too high up the
heirarchy. Cherubim and Seraphim are envisioned as spending all their
time in the very presence of God. I would say that the Vala are
Principalities and Powers, with the top Maia being Thrones and Dominions, with
Istari and Balrogs being GI Angels and
Archangels.