Many of the choices I made during this bumpy configuration journey were driven by reliance on general Linux configuration information sources as I tried to figure out what problem I was actually having at any given moment.
Since I have an inventory of additional uSD & NVME cards I assumed that as my Linux understanding crept up from the near-zero mark I would be starting over at least once reevaluating those choices targeting a less 'chaotic hackers playground' configuration.
Examples of this were installing both GDebi / Synaptic package managers as well as GParted / KDE Partition managers.
I had no idea in either case which would work best or what I would like to choose in the long term, but when I'm in the early learning phase I always know that there will be outright mistakes and sub-optimal choices to say the least.
BTW, I do get your point about the RPi config tools not being necessary for those who know where to go in the Linux config hierarchy to achieve possibly better optimized results but the installation of those tools could always be rolled up in a script as I suspect their inclusion into the XFce application menu for those at their first rodeo.
Now one last actual question:
Even in the situation where someone was going to take a pass on installing the GUI config tools wouldn't it still be valid for all Raspberry builds to have updated APT sources and PGP / keyrings signatures to enable archive.raspberrypi.com (and maybe archive.raspbian.org).
Please correct me if I'm off the mark but wouldn't that be the appropriate 'deb' sources for things other than GUI config tools. Guessing out loud: firmware, eeprom (etc) and possibly purpose built Pi kernels or OS components.
Just wondering.