Thank you for the detailed reply.

1. I've used onedriver previously, or rather I do use it on my backup machine. While it works well what I'm missing is a progress indication for the download of files, I occasionally work with bigger video files f.ex. Also an option to keep directories synced permanently to the device would be great. In OneDrive you can check a box in the context menu to 'make files available offline'. It keeps the file/directory synced and available offline. This is again useful for bigger projects. I could of course move those to a temporary location on disk but I do like the set and forget nature of working in automatically synced directories.

2. I assumed that's best practice, thank you. What I find overwhelming is the amount of choice. Which is a general Linux "problem" I suppose. Yes, it's possible and elegant to manage everything through the package manager and the default repos. But if I search for a specific program, like f.ex. a clipboard manager, I might just get recommended something that is not there. And all of a sudden I have an appimage. Or the nextcloud client for example, it's on the flathub but only the appimage supports the above file on-demand feature.
   Btw, how can I be sure that software from the flathub is kept up to date? My understanding is that it's often community maintained?