Brew does not affect avatar, so no Blood Pacts. Don't even bother summoning an avatar if you use a brew.
It's basically like any other job: elemental weaponskills reign supreme. Cataclysm is awesome, Earth Crusher works well too.
For Cataclysm, I've found the best atmas to be Cosmos, Smiting Blow, and Griffon's Claw. If you're missing any of those, standard MAB atmas like Ultimate also work well.
Cataclysm will do about 11k to Shinryu with wings down.
____________________________Pergatory (Asura, Kupo LS) WHM99 ~ SMN99 ~ DRK99 "If you want to know me, look inside your heart." -Lao Tzu