There is no sure shot formula as to which currency pair will earn you profit.It is like to each one his own! When Forex trading deals with currency trading so one must select a currency pair very carefully . One must select currency pairs that show sharp and strong signals.
I would be tempted to pair sterling and the euro - sterling will be volatile but has been battered since 2016 in light of the EU referrendum. I think sterling offers better value than the euro - remember EU central bank QE?