Except for bitcoin, I also like ethereum. Ethereum is also a very potential coin. I'ts technology is modern and it has many benefits for humans. So many people are using it.
Both coins are must to have in a portfolio as this will help you balance the portfolio along with some other altcoins and ICO coins you may want to have it. Also at present GAS has fallen a lot and it has a good potential to multiply shortly . So if possible invest in this coin.