Ethereum.
It's my first choice within all the altcoins. There's no need to doubt about this coin, I've been holding ETH and I'm optimistic for its time of recovery.
I second with this since Ethereum is the most competitive coins next to bitcoin and same as what you in your folio Ethereum is also in mine.but i also consider litecoin to be in the next since this coin has ben in used for long in gambling area,that we know how much spenders people on theirs in terms of betting day by day
Litecoin would be my next choice too but among all, I'd say that Ethereum is the best altcoin so far. I recognize the pump made by Litecoin for few months, it has been a good run for it.
There seem to be some discussions that due to the replacement of XRP in the 2nd position of Ethereum before, they prefer to get into XRP instead of ETH.