I agree with above points, except that for most coins to become mainstream, they first must have appeal to the people who know what they want to mine. Ofcourse there were some exceptions to that.
I think that if you want a coin to be a succes you should focus on consumers, not miners. Miners don't add much value ( put money into it ). If people buy a few hundred dollars of your coin because they have a real life use for it.... isn't that 100x more diserable ?