I've created Makefile's for Duo's 2 factor authentication (with + without PAM) and Mosh.
Using 2FA with SSH keys/passwords greatly increases security as SSH access will not be granted with just theft of password/key unless they steal your 2FA phone/Yubikey too.
Mosh is a UDP replacement for interactive SSH terminals. It's more robust and responsive, especially over Wi-Fi, cellular, and long-distance links burdened with latency. Build instructions for Mosh can be found at https://github.com/mobile-shell/mosh/wiki/Build-Instructions
I hope to get these packages accepted in to OpenWrt at some point and would appreciate you testing on different architectures/platforms. Feel free to post your issues here or on Github.