Never put that much (50k $) money in one coin. It would be very risky and you could lose instead of earning. You can try stratis, tezos, ethereum if you can stay there for 2 or 3 more years. These threee will generate nice profit.
"Qouted for the win", Diversify your portfolio. The stock market is looking at 10-15% a year returns on your initial capital investment. We are looking at 50%+ easily a day. Remember the internet boom in the 90's? This is the new "internet boom" in (2010-2020+).
Crypto-Currencies are the new digital asset class. New Millionaires and Billionaires in the making.