If you really wanted to mine, then go with it. Just make sure you've done as much research as you can, and have done ample computations to have an idea on how much you're expecting to make, and when you're going to make your investment money back.
This might help you:
https://www.coinwarz.com/calculatorsOn investing in coins/tokens though, personally I would invest rather than mine, but that's just me. It probably goes down to where you think the markets will move to. If you think it's going to go up soon then you might want to invest a significant amount. If not, then probably go with mining.
In my opinion though, if I had $50k to invest, I'd invest a good amount outside cryptocurrencies, for lesser risk. Probably for eCommerce or something. Just my opinion. In the end, it's your decision.
![Tongue](https://bitcointalk.org/Smileys/default/tongue.gif)
Best of luck.