They just did some updates that make this more desireable, but not really an "Armor Farm" because of low mob counts (500-600 per wave), also It crashes, has very low DU to play with.
Party:
1 Hybrid Monk (Tower Boost and Hero Boost stat as high as you can get them) had him on the hill at hint 4, right near where the forge is.
2 Hunters with cloud pets (auto firing, one facing West, one facing SouthEast-ish), at each hint 5
1 Summoner with cat/huntress pets (cat boosts the DPS and Huntress boosts the towers)
Monkeys are cool though! Super Cute! Probly the only reason to run the map, but you can get them at wave 25, so maybe just use a Survival build instead.