Controlling the volume of null-sinks monitors when spliting channels to speakers and headphones

Hello, I am using the configuration described here https://wiki.archlinux.org/index.php/PipeWire/Examples and it works brilliantly. However, to control the volume of the headphones/ speakers individually I need to change the Front (+LFE) / Surround channel volumes, as created sinks do not respond to volume changes.

I wrote this to automate the progress https://gist.github.com/nicman23/a2a80200e1d5d1f65b75846c5f2387b7 but it would be nice to have it available through plasma's ui as did my previous pulseaudio setup that used module-remap-sink