After Bitmain has increased the prices for Antminer S9, I would suggest you to wait for a while, some new miners from Avalon and HalongMining are coming this spring.
I'd recommend you to buy Ripple or NEM, but the prices are too high, so it would be better to hold and wait for a correction. Also you may find some suggestions in this thread: https://bitcointalk.org/index.php?topic=2406729.0
There are many altcoins that have a great potential such as DASH, IOTA, Monero, Litecoin and etc. Bitcoin has nothing but fame and the largest market cap, and one day one of the altcoins may replace it.