I completely agree with this. The only think I really hope for is a clear criteria of what is needed to be listed.  Is it a specific market capital threshold? A listing fee, good history and for how long, certain technologies? This would help future altcoins get access to fiat->their altcoin.

Personally, i doubt that if a coin has a built-in decentralized exchange, coinbase would not have an incentive to add them to their own exchange so that might narrow down a few coins.