My ranger is level 5, all others are level 4. I'm using melee weapons with fighter / paladin and range weapons with the other members. I don't have a special tactic. I just send my fighter and paladin in, and see how the fight goes.
Ranger: Vicious Companion, Swift Aim, Swift and steady, Stalkers'link
Paladin: Deep Faith, flames of devotion, enduring flames
Fighter: rapid recovery, guardian stance, hold the line
Druid: Fire element, catform
Priest: Brilliant Radiance