I recomended to buy ethereum, you can go all in in ethereum, buy ethereum right now wait it rising arround 30% then sell back to bitcoin and holding bitcoin, im sure ethereum will rise his valie before bitcoin rising, after bitcoin starting to rise, all altcoin will get danger situation.
I think the suggestion for all in to ETH is not the right thing because it is too risky if bitcoin goes up and ETH is declining better if invested in BTC or into other altcoins that have the potential for medium or long term investment.