I have made a Pi3 B+ image 64 bit with lxqt desktop, but also for an headless image command line only it would be impossible using audiolinux/archlinux arm, since
"When ramroot is enabled, during the initial phase of boot the amount of detected RAM on the computer along with the size the root filesystem to be copied is shown on the screen. If there is at least 500MB more RAM than the size of the filesystem, the user will be prompted to load the root filesystem to RAM. (Confirmation prompt defaults to yes with a 15 second timeout.)
The size of the zram partition created is determined by taking the size of the root filesystem plus half of the extra available RAM (to a maximum of 6GB)."