What I'm doing is instead of having 4 GPU's mining different things at the same time, to rather split my month into 4 sections and mine with all the cards the same thing for that section.

For instance:
week 1 Eth+DCR,
Week 2 ZEC,
week 3 ETH+SIA,
week 4 ZERO.

That way you can easily optimize your overclock and power draw for that week's mining