What if the price drops?
For prices to drop, holders need to sell the token. So, if the price drops it means that there will be fewer people to distribute all the mined Ethereum, so you will get a higher return than you had imagined at the beginning! If you think about it, the best thing that can happen to you is that someone sells their currency because now that person will not receive their ETH and there will be more to distribute among all of the current holders. If you are mining for the long term you will always win regardless of the price of the coin!