Do you people have any tips for a long time Linux user to feel comfortable / at home using Windows?
Some things important to me are: 1. Shell: I believe the WSL can help me here. 2. Keyboard centric life 3. Tiling Window management: I use bspwm and cannot imagine a life without tiling
You should probably see what you can do with Chocolatey/Scoop depending on security policy. Package management in Windows is severely deficient compared to GNU/Linux distros but those are possibilities.
Redirect the future data generated to the same or additional folders on the storage partition(s).
Keep a record of what default settings are changed to accomplish fully effective data storage to places other than C: in every way.
These folders can easily be backed up (copied) manually to external drives, retaining the same structure as on the working storage volume.
Still install all programs to C: and C: can retain their settings along with your Windows settings.
You manually build a simple straightforward text record of the mission-critical installs & settings you make to Windows and the programs on C: anyway as you go along. Much easier to reproduce settings from your own log than any Windows install log.
Now C: then only grows with the size of Windows, its updates, and the executable apps installed but not the data generated. Also the garbage like Temporary Internet Files stays on C: but you're supposed to have that kind of thing excluded before backing up. So a complete backup of your C: volume is as small as reasonably workable and only takes a few minutes to save as a WIM file using DISM.
And even less time to unWIM the backup file onto a freshly zeroed & formatted partition when you need to get your system back.
DISM is made especially to back up the structure of a Windows volume like you can not do manually but would be good if you could. Folders on C: other than Windows' needs come along for the ride and fatten up the backups so you have to be judicious about them.
Done right it's the quickest way to recover when you suffer from a Windows failure or corruption on C:.
So even in case of a complete HDD failure you can rapidly go from a new(ly) zeroed HDD to a partitioned, formatted equivalent of your former system as of its latest backups without the woe that can ensue when you let C: in general become fat with anything but necessary apps or let the C:\USERS folder become scattered with things that you are not willing to discard, while trying to depend on less-manual backup plans than DISM.
Windows, and therefore the whole C: volume has always been best treated as disposable regardless of how much people think it is worth.
You probably can't rehearse your backup & recovery process too carefully or too far in advance.
After using DISM to recover, you can use BCDBOOT to create new boot files.
Some apps are not robust enough to withstand this process without additional re-enabling of some kind so test them all, and really shoddy ones which need to be reinstalled anyway can then be excluded from backups to further simplify the backup until a more appropriate app can be found worth including instead.