Probably not the fastest build out there, but it certainly works. I got 13-14 min combat times on the beta. 

• TB + Guardian builder wave 1, then upgrader until max. After that, running around with a DPS Huntress / Apprentice helps with killing certain bosses. (2 Splits) On final wave, I would do a 2x Huntress (or Squire, especially if you don't have Hermit for Pylon) Guardian Summoner and a builder Guardian. 
• Mortars are surprisingly good here. Any boss that gets close to the stack just gets decimated. HOWEVER, Super Copters, Demons, and Spider Queens counter them pretty hard so they're only THAT good for waves where the bosses approach your stack. 
• I love Guardian on this map. Holy Cannons can replace Mortars, but they're about equal. You can definitely do some messing around with possibly replacing Golem / Spore for Bulwark / Obelisk if you don't have Hermit, but do have Guardian. On the other hand, Owls are just superb. Even though they don't have the highest boss damage, they do very well with general mobs, Super Wyverns, and the mini Spiders from Spider Queens.
• If you want to go for Flying Pumpkins / the secret boss, Empowering Shrine helps a bunch with that. The boss was never really that hard, but shrine makes it a breeze. As mentioned before, DPS Huntress or Apprentice for this.
• Ironically, this map is great to farm for Guardian since it's one of the best builder sword farms. If you can run it at the same rate as I can, you're expected to get more Corrupted Axes / run compared to Valentine Citadel and Fish. (0.25 Corrupted Axes / Min vs 0.2 Fish / Min with my typical times for both maps. Axes also have better ++ rates... AND you're also farming Dragon Halberds that have similar rates to axes, which is a nice bonus.) 

This map is still definitely one I'd recommend higher stats (6-7k+ Main) to farm comfortably, but it's nice having another option for it. :3