If you have a look at the flavour maker ppa you will find bluez-firmware and pi-bluetooth packages. I seem to remember the raspberrypi-sys-mods package is involved too. These will need updating for the 3B+, see https://wiki.gentoo.org/wiki/Raspberry_Pi#Bluetooth . Raspbian/raspberrypi should have updated/equivalent packages in their repos (http://archive.raspberrypi.org/debian/pool/main/ ).
Audio needs a line in the config.txt. See Raspbian/u-m 16.04
Swap - https://wiki.ubuntu.com/ARM/RaspberryPi#Swap . Try zram instead.