HI,
To me, Bitcoin is best for invest in Digital Currency than ethereum. Here the reasons:
* Ethereum is not just a digital currency
* Bitcoin is deflation while Ethereum is inflation
* Bitcoin is simple and limited
* Bitcoin has a first mover advantage
* Bitcoin have bigger community and Its easier to get started
* Ethereum is less known and younger
Hope you get your answer.

I agree with you.
Ethereum is not just digital currency, it is also used for contracts. And this contract are the basic tool to nowadays ICO's for better or worst it has that use. The potential is huge but it is , as you pointed out, less known.
Bitcoin is digital gold, I cant say anything that you haven't already know about it.