Alright, well ty everyone!
All my data is backed up. When I get home today I am wiping the server, installing and configuring Nethserver and wiping a Win 10 laptop to connect to Nethserver.
I think I am going to start by trying ZFS for my 4x 4TB drives with the OS on the 120GB SSD.
Presuming it all goes according to plan, I will wipe and connect the other Win 10 laptop tomorrow.
I am then going to consider if I AD join my Manjaro laptop or not. I presume it should be feasible, as I have been doing, to simply connect it to the desired shares without connecting it to the AD/Domain? Basically I have it (Manjaro laptop) setup how I like and are not too keen on wiping it and then re-tweaking it if I can avoid it.
I will likely try both BackupPC and UrBackup and either use both or decide which works bets in my setup.
I am likely to use ClamAV on the server as per @m.traeumner recommendations as well as on my Manjaro laptop. For the Windows 10 machines I am considering purchasing a consumer solution from either Bitdefender or McAfee in place of my business server/endpoint current setup using Bitdefender.
I am then excited to poke around in Nethserver and find new modules, programs, etc to get the most out of it.
I would of course be happy to report back with the progress, would it be best to start a new thread for that or to simply continue it in this thread?
Again, thank you all. Its rare these days to find software with decent documentation. Even more rare is finding software with a friendly, helpful and knowledgeable community. Nethserver has nailed both.