I don't see how this is complicated or confusing and I completely disagree with you. I think this is absolutely the right direction to be going if coinbase (and bitcoin) want to become mainstream. An exchange is mainly for traders and most people like myself don't want to look at candlestick charts to know when to purchase or make a bid without any certainty of obtaining coins or worse compete with bots. On the other hand many people I know have kept away from bitcoin because of how seemingly complicated and confusing it is to supposedly keep secure -don't keep coins on exchange, use paper wallet, encrypt backups of private keys. This is definitely a step in the right direction towards attracting a more mainstream audience. As for a 'Pay with Bitcoin' button, are you kidding, how do you think overstock, newegg etc accept bitcoin payments - this is one of the first things they did.
- An exchange is definitely a huge opportunity and a valid direction regardless of whether it'd be useful to you. and one that would make wall street more interested in Bitcoin which would push it mainstream.
- I feel this "vault" stuff won't do much to convince people it's secure. who knows whether the security is even different? just more terminology to learn = greater friction. keep it simple.