Sure, BTC could always go up or down, and if you believe in the value and strength of BTC as a long-term thing then you would probably be well-served by holding it for the long-term, and thus avoid the "rollercoaster rides" of late (super strong price moves in very short time periods), but that is not easy, in my opinion. On the other hand, the biggest holders of BTC could probably keep prices low for a time to try to create panic selling of coins. In these cases, if BTC holds in the long-term, then the panic selling will only be a short-term thing and you could possibly pick up cheap coins. On the other hand, if BTC is currently overvalued (meaning that inherently, without the need of assistance, the price would be significantly lower than it is now) then perhaps one could sell a small portion at say, $8000 and be satisfied with that decision if the price drops in the coming times.

Ultimately, there are many factors in play, and I would guess that the safest move is to account for either possibility, i.e. a large rise in the long-term, or a price drop and staying low, closer to the "true value" of BTC (this is just a theory). Plenty of information and data to search through to keep one busy for quite a while in this area.