Place your tb monk where the green arrow string is and it will reach both the warden towers and the traps. You will be able to complete the build during first build phase so you can swap right into your upgrader. Upgrade the buff beam with warden towers, then move over and upgrade the other buff beam and traps. After that you just upgrade in whatever order. 

Last wave: I go for spears so in my case I use builder warden, tb monk and 2 monks with hunt guard standing close to warden towers. If your 2 monks stand too close to towers, the harbingers might kill them so try to keep a little distance

Using these aura placements will allow them to reach right infront of all the spawns (with pylon) except northwest spawns which are getting nuked by traps instead.

By not having any physical towers northwest, the bosses will aggro to the other side making the wisp dens hit them more consistently