I wonder why the Ricochet developer has chosen to use tor again, i have strong doubts about its security, add to that it doesn't seem to do anything different than the already existing torchat.
The I2P protocol would have been a much more interesting and secure choice imho.
I'm impressed by the Tox effort, going to keep a close eye on that one, open source, multi-platform, very good initiative!
Bitmessage is great, but slow as #@$! and not available for mobile devices.
Bleep is out of the question, closed source proprietary spy junk.
If you want to use I2P-Messenger, you need to have I2P installed (and last time I checked, that required a JRE too). Tor appears to be easier to implement. As far as I understand, I2P connects users directly through the network, while for a Ricochet chat, both sides work out a random rendevous point in the Tor network. That means there are 6 hops between both users.
Tox looks good indeed. You can add another layer by tunneling it through Tor too and maybe a future release implements it directly.
Secure messaging has to be as simple as possible because your everyday WhatsApp/Snapchat user does not want to invest time into security.