PoE DaSkyMan builds

I have wanted to play caustic arrow for a while now but it doesn't seem to do enough damage. I threw together this POB and it doesn't look promising: There's little gear, but even with expensive stuff I don't see it doing more than maybe 3 million DPS, and since its tankiness and speed isn't great, it doesn't seem worthwhile to play. Has anyone found success with Caustic Arrow?