Hoped that you stayed strong along the ride and had made good decision with your fat stack of bitcoins, diversifying is always a old school method to keep your funds stable with market movements, going into big chips like Ethereum, Monero, Dash certainly wouldn't got wrong over the years, supposing your style of holding had paid your efforts, it's good to invest more, learning more from other altcoins/projects to make good market decisions on trading, holding is fun and exciting for me.
Of course diversifying is almost good and what other have preached, don't put your eggs in one basket. I believed in this saying that's why If I'm the OP, I will sold a few and re-invest in in either few altcoins or real state. We never know that future so its good to be at least ready in case something bad goes to your first investment.
In the past, I have a bad experience with my investment because I never diversify. I thought that my investment is already good and can last for long period. Unfortunately, it came dawning at me that I should diversify, but its too late, I already lost almost everything and I did get out of that investment.
So its never too late to spread your portfolio in the following: crypto, stocks, mutual fund and real states or even put up a business that will keep the cash flowing on your end. Old school but still effective in my opinion.