Why is this better than the memo encryption we have in bitshares right now?
How would memo encryption prevent someone with an ability to analyze traffic to see who you're sending messages to? Could your ISP see it? Could anyone see it?
Memo encryption while I don't have the details on it, if it's just encryption then it's not going to be enough. It's not just important that you're encrypted but more that you're immune to all forms of analysis. If it's not possible to know who sent or received what then you're far more secure. Alice and Bob would need to be able to communicate in the dead drop method where no one can link Alice to Bob.
And this would also be something which can be a mainstream app which is completely separate from financial services or anything like that. It would be for people who need secure communications and who are willing to pay for privacy through micropayments. In theory perhaps it could be built into websites or be an app on mobile phones, with no link to Bitshares at all but which would still provide fees to the network.
If you know a lot about encrypted memos, your knowledge could be useful to design something far better than that. The goal is to be the "Most Secure Messaging On Earth". There are a lot of different technologies to review and research such as DTNs (disruption tolerant networking), which can actually integrate into an Internet of Things, so that by paying micropayments to various things your messages can be relayed like how a DTN would do it.
Of course all of this would depend on how much of a budget there is, and if it's a FBA then if it's a very popular feature it would pay for itself and have enough of a budget so that it literally can evolve into the "Most Secure Messaging On Earth".