For 72player slaughter melee definitely requires a different playstyle than the other match modes.

Personally, I feel the first/only priority/role/job as melee in 72 slaughter is to not die. Or at the very least, be extremely difficult to kill. You don't want to be the food that starts an enemy Caster's Battle High/Fever or fills a Melee's LB bar so they can go 1-shot your healer.

Most of the time enemy DPS will lose their patience trying to get at it you and overextend or do something silly that get's themselves killed by the rest of your team. (Alluded to that on page 1)

May not help your Rampage, but assisting fills the LB bar too, so eventually you'll fill. And LBing wisely and target cycling wisely, - but mostly just keeping yourself alive - is my trick for a good k/d ratio

My approach at least.