Ethereum has more functionality than bitcoin but its far from certain if either bitcoin or ethereum will be the future of crypto there as just so many choices now. And bitcoins first mover advantage is nothing to scoff at.
Nobody really knows the future, but to be safe buy some eth and other alts. Spread your eggs people.
This here is the best advise. As much as you may love the coin you are promoting no one has a crystal ball, spread it around and diversify your investment.