Well, I think ETH is the best choice, it is more decentralized among the three. BitMEX once said that Ripple is way more centralized than being a decentralized. And even some blockchain experts and enthusiast, doubted that even DASH is not-so decentralized one. So, I would love to choose Ether.
Being decentralized compare with ripple is one of the reason to choose etherium as our investment
Another reason is etherium already make the cryptocurrency booming in general with its smart contract so choose etherium rather than the other is better choice. We are to make money so choose the best from the best.