This is not Raspbian what we are using. It is a custom build linux distribution.
I will do a writeup of how to compile it if I get some time but the basic steps are in here: https://github.com/rpicopter/buildroot"
"Did you adjust acro and stab PIDs? You first need to make it fly well in a stab/acro mode before trying to tweek altitude hold mode. Do you have experience in other quadcopter controllers like MultiWii, ArduCopter, naza, etc?"
"Looks good. I would not worry about slight Baro movements. You will need to test fly to see and adjust parameters. You might want to read the ArduCopter altitude hold manual. It gives good overview of what parameters should be adjusted."
"You do not have to use barometer. You can use any other altitude estimation. Using arduino means we would need to write all the different drivers. In this case you might want to look into MultiWii.
AvrMiniCopter vision is to be a minimalistic…"