I have stayed with OOs and quite happy with it right now. Most apps are working even on rooted phone and encryption works I believe.I'm with you on the device encryption and also asked the same question. Let's see if anyone has tried.
For everyone's awareness without encryption is possible to access the filesystem via the recovery and access all files. Is also possible to remove the screen lock by removing the file lockscreen.db from /data/system and have access to the phone and all app contents. Really scary for such a mobile device