just checked for you. Best algo for you is etc. looks like it gives 17.5mhs on eth based algorithms. 17.5mhs on etc right now giving 0.74$. nicehash does not support etc you will need wallet and and pool for etc. with 28 sols on zhash you are making 0.70$. so there is no point to switch.
How about conflux? I'm not sure if gtx970 will be good on octopus algorithm, that coin is very profitable and almost near the profits you would get when mining Ethereum, way better than ETC, Zhash and ravencoin