There is a device called the Turris Omni which is also based on OpenWRT and the code is Open Source (and actually available online)
The device is ARM based however, but perhaps the customisations or the full OS could be ported to MIPS64
at least there would be continued development.
https://www.turris.cz/en/https://www.indiegogo.com/projects/turris-omnia-hi-performance-open-source-router#/Worth a look just for the video on Indegogo lol