ETC is the most profitable right now to mine, at least for me.
Wise, unfortunately, a partner of mine, shelled out 5k to add two more rigs to our collection and I needed to find/source GPU's somewhere, he was not willing to wait for anything, but even so, I think price is going to be an issue as well as finding those 6 and 10nm chip cards.
RX 570's are cheap, you can still find them and with some undervolting and overclocking, you can get 30MH/s out of them @ decent power consumption.
GLTY