Imo it's always best and the most stable (in crypto terms that is) if your portfolio is built some bigboy coins like BTC/ETC.
Having said that, if you have a decent chunk in them you might as well experiment with other coins and given all the thousands of scams out there Link (and to some extent ADA even if I disagree) are pretty safe choices.

Just avoid switching always when 1 is rather low and the other is rather high.


Good luck man!