You should try to make your own researchs about that, but ethereum might be your best altcoin to invest right now since it is one of the most safest ones, and the most promising ones too.
I prefer to invest in safest coins instead of those shitty altcoins that are always underrated, by this way, you will always know that you are investing in something safe, and that will never go to zero.
Monero is a good option too, but it has not been moving during the last weeks.
I second the motion.
For me ethereum is still the best altcoin to invest with.
Althought the value of it was quite stable.
But oftenly now, the ethereum price are gradually moving up.
And expected to reach $1,000.
And hopefully it will come true , so that a lot of ethereum holder can exchange their coin into the higher amount.