Quick question, would it wiser to trade pairs where one of them is a Fiat like USD or EUR? I understand that when trying to get more BTC (or ETH) you should trade BTC/ETH for example.

But because BTC/USD is going up and down so much, ETH/USD or ETH/EUR would seem wiser. Except of course if you want to hold BTC for later, like a couple of years: but predicting the future is hard..

Everybody needs to pay bills with 'real money' since it is not possible yet to pay everything using a crypto currency.