[DejaVu123]

You can use a Kobo with an imaginary email address. Then it's pretty private. Do turn off autosync and all reporting features.

Using the imaginary email is a good idea. I didn't realise you were able to turn of reporting features on Kobo, would this be found in the settings menu? Only I heard that there was some uncertainty on how much data they send, leading me to think they may not allow it to be turned off easily.

I use my Kindle (real ereader, not app) to buy an Amazon book, if I can't get it on Smashwords. I select "download to PC and transfer via USB".

I will probably use Calibre, I just wanted to make sure I did not have to always use it when getting a new ebook on my device.

So I read EVERYTHING on the Kobo. It's also best for annotations via Calibre and Kobo Utilities.
I keep WiFi off except if doing a lookup in a book (Kindle or Kobo). Web pages are ghastly on ereaders.

The annotations feature sounds useful. I as well will probably use the web browser mostly for just looking up books (apparently the web browser on 'Kobo Glo' is only experimental, but it should be usable).

Madness downloading on the device. I download on my Linux laptop. Often the PD ebooks need cleaned up (Calibre can do this in most cases. In extreme cases I export RTF, read that into LibreOffice Writer, fix styles etc, save archive as .odt and "save as" .docx to import back to Calibre. Then convert to epub.

For larger collections of ebooks (such as from Gutenburg), I will probably download from my laptop as well. In what way is it difficult to download directly from the ereader, is it due to the filesystem?

The Kobo Libra H2O seems good value and Kobo better than other brands.

Thank you very much for the advice. I'll have a look into the Kobo Libra H20 as well.