Try Webtop. It'll give you a literal Linux desktop in the browser and it works pretty well for me.

Seafile has SeaDrive which mounts like an external drive and works just like other similar services like OneDrive.

I like D2 because it is declarative and I can keep the model in source control.

Dozzle may be a bit basic for your needs, but it could be one tool in your toolbox.

I like to prefer images from a known source like linuxserver.io.

https://silverbullet.md/ and I may start using https://d2lang.com/ too.

Transmission has been rock solid for me. Give it another try.