Agreed, no official flavour installs Synaptic by default, because they are official flavours.
I remember the beginning, when Cinnamon was just starting. I installed every single one, and those before, when Mint was with Gnome 2.
Test until they break, or they don’t break. It is neither Mint nor Ubuntu, but it works, and if it stops, I’ll start again. Have enough 20GB partitions.
I also have an unusual Ubuntu that runs
env GNOME_SHELL_SESSION_MODE=ubuntu /usr/bin/gnome-session --session=ubuntu. That too is holding on. Updating everyday to check, if any of my disco installs would break. Few days left for feature freeze, anyway.
For Debian or Ubuntu to have Mint packages in their repos, Mint devs have to make them first for themselves. And, those Mint packages would always be compatible, for the next Cinnamon-Mint LTS would have to be compatible with next Ubuntu LTS and next Debian.
Name can be decided on later, first the distro/remix has to be made. I am giving evidence that Cinnamon 4.0 works quite well with Disco, so @itzswirlz go ahead and make the Cinnamon Remix.