I'm enjoying it. Here's my broken build:
Wand with 3 shots
As much attack speed as you can, including the standing-still one
Bullet penetration.
Larger bullets (up to 3, don't get the 4th, it'll shrink them)
Keep most enemies inside the cone of bullet death, and dodge the other incoming. This alone is pretty much all you need to get past 60, as incoming bullets basically can't hit you.
After that (and as you go), get leech. You've got dozens of hits per frame, so your health basically stays capped.
With this, I've hit lvl 100 and am basically invincible, standing in a corner and just tanking hits. I'll probably just intentionally die now since it's running at a couple seconds per frame, though with 5 orbs also causing leech, I'm not sure it's possible.