Okay, at least that gives me an idea, thanks
I'm going to do the same later this year as like you my setup is 10 years plus, though I'll re-install Arch again What MB, GPU card etc did you buy? , as I'm out of touch with the latest equipment now, so would be grateful for a heads up
Use timeshift, install it, just chose where you want the backups to be installed, preferably a second HD or SD Flash. Chose when like once a day, week at start up for instance and forget it. Then if you screw up your Linux, just start in console mode, timeshift --restore and five mins later your up and running.
If you want just your data to be copied, then Cron
Both are standard Linux programs, often already installed depending on what Linux you have
Though to late to help you, when you get it working again, install Timeshift, so that instead of faffing around to try and suss out what went wrong, you just start timeshift -- restore from the console and a couple of minutes later you'll have your working setup back. It's saved my bacon quite a few times in the last couple of years, especially when you can't login to your DE.
Grab a second SSD or HD, that way, keep windows in one as it will be probably be supplied with the computer. Add Linux to the other disk, Debian maybe, EndeavourOs much better. ThNo dual boot. And when starting to computer just choose which disk you want to use (F8 or F12 often) and later if and when ready, you wipe the windows HD and use it for backups
Like you i switched from about 30 years of windows to Linux almost three years ago, Ubuntu, Mint, Manjaro, Endeavour before ending up with Arch which I find perfect. I also have two PCs running Debian for HomeAssitant setups in two homes but I don't like Debian I sometimes use my wife's Windows setup for Garmin Express as that's the only windows program that I need. So keep on going, Windows is not missed,
Timeshift. Easy to set up. Easy to use, only takes a couple of minutes to 're-set' your system back, if you break it. If you want just to backup files, documents etc then Cron. I use both. They are standard Linux programs and easy to use
For note taking, Joplin is pretty good, in fact I went from Simplenote to Evernote (over kill and not free) to Joplin using Dropbox for the syncing (syncing is done by Joplin, so you don't need a 'syncing' app) between my PCs, all Linux and my Android phone. Simple to set up and free. I do not use it as a Journal as that is extremely poor, but for notes, it's perfect
I use timeshift, on Arch and a Debian setup . It's simple to set up, I do a automatic snapshot once a day, so if something breaks, just boot into tty and restore the previous day's snapshot, takes about five minutes. Not sure why you say ext4 doesn't work as it does. Haven't tried the other programs that you talked about
I went from Manjaro to Arch. Installed by command line (took a few tries to get it done... ) I tried their installer but it wasn't very good. Have also run Endeavour on a second pc for a while but I prefer pure Arch.
Use timeshift, easy peasy to set up. It's saved my bacon a couple of times now, only last week, when the kernel 6.4 came out, but my old nvidia driver wouldn't work with it. You just jump into tty, run timeshift --restore and chose a previous backup, takes all of ten minutes. I have it doing a back up every day to a second HD, keeping the last five, doesn't take up much space. I don't think there's an easier option than that.
Timeshift for the system, works perfectly, if you screw up the system, bad update for instance just start it, and you'll be back up running in less than ten minutes. Simple Cron backups for data, documents etc, just in case you delete a folder, document, image etc . Both of these options to a second internal HD