I farm Powerslave on auto as recommended by my fellow troopers here, it was worked out a little while ago in the forums that per sands of time this is the most efficient way to farm for gold, NOTB is probably better if you can put together a team that won't fail against the beast, short of Alexander in your team I don't see how...

Navigator (when you get him) is my choice too, there would be others but I'm not too familiar with alternatives, FOTD is good too but like Yup said a bit slow on his moves, I choose to play one Ally beside Navigator thus leaving the other Ally spot open for troopers, I use Warrior Lilith, besides playing a third toon means the third toon never gets a look in anyway after Navigator and Lilith a finished with your foes....