Optional stuff

Speed up boot time

echo "disable_splash=1" | sudo tee -a /boot/config.txt
echo "boot_delay=0" | sudo tee -a /boot/config.txt
echo "initial_turbo=30" | sudo tee -a /boot/config.txt

Disable unnecessary services

systemctl disable cloud-init-main
systemctl disable plocate-updatedb.service
systemctl disable plocate-updatedb.timer
systemctl disable NetworkManager-wait-online.service