One of the problems with cryptocurrencies is the "hodl" mentality. People are mostly invested into cryptocurrencies to make quick profits and sadly this attitude of treating cryptocurrencies as fast-paced investments that you can net 100x gains off of is actually holding it back. When Satoshi created Bitcoin they envisioned a digital currency you would use to buy and sell things, a digital equivalent of fiat.
I am currently working on three concurrent startup ideas that all involve only cryptocurrency, marketplaces and auctions that require the users to transact in currencies with low fees like Litecoin and Verge Currency. I am trying to do my part, but the instability caused by hodlers and day traders isn't helping in the short-term.
One of the other major hurdles to mainstream adoption is you need to jump through hoops to even get Bitcoin or other currencies. You have to show more identification to meet KYC/AML requirements than you do to get a mortgage with a bank, it's crazy.