Don't forget there is coinbase pro which offers more advanced usage and with pairs. there are 2 coinbase that makes one, there is coinbase pro with assets and pairs not on coinbase basic. Would be nice to see coinbase support steem. They could create a support line here on steem, marketing, delegated proof of stake ? can they run a witness node ? correct me if i am wrong. If those are possible i don't see why shouldn't be going after it. social platforms hold more value to exchanges if they don't know it yet. more satisfied clients should equal more value for them.