I'd probably put some form of magic attack as well, either from the general bonus or via earth magic attack, but this was partly because I did have a reason where I might want to use CNJ over WHM in something other than a lowman. Specifically, in situations where damage per second is of critical importance, but they still want enhanced protect/stoneskin and ready access to cures. Case in point, assisting on a BLM burn on Garuda, where my only options for attack were stone and stonera (She's healed by wind attacks). Going as CNJ would have allowed me to cast thunder, giving me something to cost when both my stone spells were on cooldown. Probably a bad example because they've supposedly fixed Garuda, but who knows when another such situation will crop up. Technically, a serpent sergeant staff would be better if the MP drain doesn't turn out to be an issue, but only so long as sanction is up.