How to build a truly secure and private instant messenger?

There are many messengers on the market, but none of them combine simplicity and security. Privé is a true secure communication tool suitable for everyday use.

Current “secure” implementations involve servers and store a copy of each message. And a copy of each message automatically goes to NSA (or KGB).

So my point is to derive true security and privacy. There are several technologies that I’m going to use to achieve it.

1. Everything opensource.
2. P2P. Clients establish direct connections with each other and send messages directly. A message never passes over a server. I’m looking at WebRTC Jingle. It provides P2P functionality over Jingle for iOS and Android.
3. TOR. All connections is done over anonymous Tor network to mask origin IP addresses. TOR also provides encryption, so no data can be sniffed.
4. OTR to encrypt messages second time and provide authentication.
5. We are building on top of ChatSecure for Android. iOS version is built from scratch.
6. We are using Openfire XMPP server to help clients find each other and establish direct connections.

Am I missing something? Any ways to enhance this architecture in terms of security and stability?

Please share your thoughts in comments.