I recently joined the crypto ranks and bought some Ripple. While I am waiting on it to recover and spread it between Etherium and something else to be determined, I started mining with my GPU and CPU. I downloaded NICEHASH since it was pretty easy and I ca move BTC out without having a ton. So I have a few questions:

1) I there a better place to mine or a better pool to join which would be more profitable. I joined NICEHASH because I am new. I have seen WHATTOMINE but it didn't make a great deal of sense.

2) I have seen a ton of buzz around the Baikal miners. Giant B and Giant X10. Nicehash had profitability up around 12K per month on Giant B and it has dropped in last couple of days to 2K per month. I had considered buying one on a zero interest card and paying itself off but the POI now looks like 6+ months. I am not sure it will even stay at 2K per month. I expected a drop off but was hoping for 4-6K per month to get it around 3-4 months ROI. Is that pretty standard, what is a typical ROI on hardware? How often does new hardware come out. Seems like the S9 has been around a couple of years and still a pretty good machine.

3) Any recommended reading to help me understand crypto better? I see the markets move but have no idea as to why so it is pretty much buy and hold or guess and trade.

Thank you.