Is there a way to install MODEP with all the plugins on an Arch-based system? I am not sure that I need an RPI but had a good experience playing guitar through Guitarix. MODEP looks like a better tool for this purpose.
You can build it from source yourself, but it will take a while. You can see how the deb packages are getting built here:
You will find all the necessary PKGBUILD for Archlinux in AUR repository.
It is called mod-app-git and mod-ui-git because it is the moddevices original but do the same job.