Dynamically shifting coin to mine?

[siforek]

I used to mine Ethereum but switched to Zcash a few months ago. It seems to be the most consistent in profitability. I've often wondered if a simple program that you'd set a threshold that once reached(aka coin is X more profitable to mine) it would switch your rig(s). I know there's a lot more factors at play & when/what you sell your coin for determines your actual profitability, it's just a thought/idea that if made any sense wouldn't be that hard to throw together.

Not worth it? Better to just use NiceHash? Ideas?