Besides bitcoin, of course ethereum is what I hold right now. The price is stable at this time and also the volume is large.Ethereum have smart contract technology, where almost a big projects use it. So in my opinion this is the best choice you might consider if you are looking for long term profit.
Cardano in the near future has every chance to become a leader in the market of crypto-currencies.
Indeed, Cardano is also very interesting after I read on some articles, will probably be the future leader of the crypto market.