i think the best cryptocurrency that is worthy to buy now is IOTA and and ethereum, these coins have risen so fast in the last few months of 2017, more investors have reallized the potential of these coins from bitcoin's slow transactions, since that ethereum is more popular than ever and IOTA has become the centralized coin worthy to invest.
I'm quite agree with you that Eth can be a good choice for you to invest and get high profit.
And IOTA is one of the greatest altcoin for now, it has changed the blockchain technology which is much more advanced.