I have to say I love my 1070s. Only cards I like more are the 1070 tis. But you can get 31-32MH on ethash (at least with big memory oc and a bit of core in Claymore 11.3), then push 480 sols/s on equihash with bminer with big core clock, on 120 watt tdp (I'm speaking of EVGA 1070 super clocked version) well over 4 sols / w. Great cards for efficiency, versatility, and with a bit of oompf.
As for coins, I keep my eye out for smaller ones that still have decent exchange support, and when demand is there jump on them for a day or two, like btcz. Then ZEC or Eth the rest of the time, trading half into btc to diversify the portfolio when they're up against btc.
Don't need to bump core up for a 1070 mining Ethash - they're quite happy with up to a -200 core UNDERCLOCK as they're severely memory limited, even with a LARGE memory clock increase.
I've been shifting my mining cards around, in an attempt to get the rigs to be "homogenous" so I CAN dedicate the cards that are better on ETH to ETH and the ones that are better on ZEC to ZEC and such - though it's also part of my ongoing "convert folding rigs to riser-based rigs for better cooling" and my newer "get everything set up to go into my Mark 2 shelf/rack units for space savings" initiative.