When it comes to daily usability, the best coin we have is bitcoin. This is because bitcoin has the highest acceptance rate in the world, the second could be ethereum and probably a few others. Every other altcoin are held for investment purposes and not for their usability. The world is yet to accept cryptocurrency and this could be tied to the fact that the market is volatile in nature.
Bitcoin and ethereum monopolize almost all the real purchases made with cryptocurrencies, with bitcoin holding a huge lead over ethereum as well to the point I have yet to see a single website in which you could pay with ethereum but not with bitcoin.