Ethereum is my favourite altcoin. I think it is really reliable and has a really good potential to reach good successes in the future. In addition to ethereum, I think Waves, ICON and IOTA might reach great values in the future.
Besides ethereum certainly split money into some kind of better and safer coins, besides ethereum I also keep some coins and tokens that potentially increase drastically and I'm sure some coins like Litecoin, Cardano, Minexcoin, Ethos and some coin worthy for make long term investment.