RE: Look here, Roger Ver. (My thoughts about the recent Epicenter interview)
Bitcoin will be replaced by something I call SuperBitcoin.
Bitcoin is great, it is the opening onto the world mind that there is an alternative. But, it is truly only in the geek phase. It has to become MUCH MORE user friendly.
Dash and other coins are making headway into getting things like smart contracts worked out. And this is great, but it still has a long way to go. And there are pieces that need to be added to crypto-currencies that are essential to their long life and stability, but they haven't emerged into mass consciousness yet.
And the biggest problem with Bitcoin, is that there isn't enough Bitcoin. Yes, Bitcoin is divisible enough to work for the world, but people's brains don't work that way. They ask, how many bitcoin do you have, and expect whole number 1, 2, 10. The numbers, if massively adopted would be 0.00000012 BTC which is not a human usable number.
There was a proposal a while back to replace the human-visible unit to "bits" which would be equal to 100 satoshis (i.e. 1 satoshi = 0.01 bits). It never got much traction although some UIs still use mBTC (millibits; 0.001 BTC)
I dont think it's a problem since UIs would be ubiquitously equipped with some live fiat (or whatever largely relevant) currency converter?
I certainly don't agree with the claim this is "the biggest problem with Bitcoin". There are many reasonable solutions to it.
I'm still unable to find any way to properly evaluate other coins. Even Bitcoin proved difficult, but long term valuation is just a really rough approximation of how much capital is going to flow from fiat exchanges into crypto exchanges. About the not very user friendly BTC amounts and decimals - I think shouldn't be a problem since UIs would include live currency converters..