People need to focus on coins who's product will generate revenue in the short term otherwise most will run out of money. Some ideas are great but realistically implementation will take much longer than the money will last. Exchanges are a relatively safe bet as they are something we all use.
As far as generating revenue is concerned bitcoin is best among all the bitcoin there are also other coins like ETH they also have potential to deliver profits but as in bitcoin the rate is very high and investor has a lot of room to use it for daily needs like paying bill and for shopping and ETH is also acceptable in some parts but it will take time for the progress of other altcoins because people have already the best coin.
Fluctuations are part of any trade-able commodity hence we never need to worry on seeing any coin's price is going down. When a price is falling, it is just another opportunity to buy more. That's all.