I thought macvlans were only available to rootful Podman?

I think VAAPI is still how the gpu is accessed but you can use the intel libva driver (vaapi) or the intel media driver (QSV) (arch wiki page). If I'm interpreting this all correctly.

I believe you want to use QSV (VAAPI is there for older processors IIRC).

For running as rootless, you could try adding group-add keep-groups (an explanation from Redhat about keep-groups).

Some of the recommendations I have seen are Baikal and Radicale. I don’t think either have an official Docker image, but there are a few community-maintained images.

For photos, Immich is recommended a fair bit.

If you listen to audiobooks in addition to your e-books, there is audiobookshelf. You could also consider a recipe manager, like Tandoor or Mealie, or Home Assistant if home automation seems fun.

Link to the specs

Website says 1800€ (including VAT, I believe).

Maybe Audiobookshelf? You can set up podcasts and stream them from the web interface. It'll keep track of your progress, so you can switch from web to phone and pick up in the same spot.

Edit: though it does download the podcast to the server so that you can stream it, but it grabs them automatically.