So, just for clarity, there is nothing inherantly different between a net install and a “full” install. Both systems have access to the same repositories. A net install is just a minimal viable install to get the system running without any bloat. After that, it is up to you to install the things that you need.
You should be fine with the following steps, granted I use Debian and not Ubuntu, but they are almost the same in practice.
apt update && apt upgrade && apt install xfce4
Say yes to the defaults and then you should be good from there unless you do not have universe repository install.
I got it in the end, I installed sudo apt install ubuntu-desktop this gave all the desktop components I was missing and now when I re-installed the xfce4 desktop all went well, although the icons are different.
I would still like to know how to go from the netinstall version to full version, i bet the icon issue is because some unknown components are missing in the full iso version, nearly every program I attempt to install needs some dependency installed before hand.
As for the point dutch_master raised, I fully expect to loose my data sometime, but nothing is “mission critical” this is an encryption server all the data is backed up somewhere else before its encrypted, I would rather have the speed of 2x NVMe in RAID0 that way I can have all 12 threads of the 3600 purring like kittens all day long.
Again, you are incorrect here. There is no full version. The NetInstall is a minimal viable system to boot. From there, the Ubuntu world is your oyster. Now, if you are just talking about getting the ISO that has everything that Ubuntu thinks you may want to install on an disconnected system (that is the point of the large ISO), then that is different. How ever, those packages will never be as up to date as installing them from the Internet.
Is a meta package. That means that it is an alias t install everything needed for what Ubuntu ships as the default Desktop Environment. From there, if there are other core system components that are missing, you get a dependency list of other packages that are missing that need to be there for the default DE to work.