If you want to maximize the potential of your GTX 1060, you should use the Asrock motherboard (see my signature) where you can plug up to 13 of them in one rig. The whole setup can push you around 300Mhs. If electricity is not an issue for you, you should mine as much as you can because difficulty is not going to go down.

if you want, I'm selling some of my GPU as electricty prices are killing my profitability:
https://www.befr.ebay.be/itm/192506114640?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649