This would be incredibly helpful, a note-taking game changer!

This would be awesome and would make the app better than any other PDF-annotation apps. Currently, the trick of copying a PDF page to a blank page does not work well because you are not able to search words in the text anymore (I guess when you copy the page it becomes a picture).

When importing a PDF I want to get a question of how I want to import it. See picture. This would be a killer feature for note takers.

When importing a presentation (Powerpoint or PDF), it could be very useful to insert every slide in an annotation page with space around the slide to take notes.
Professors usually shares presentations they use during lessons, but annotating directly on slides is impossible because of the small space left and it is time consuming to insert every slide manually inside annotation pages.

I attached an image representing how I think the page should be, using a current GoodNotes template.

Yes please!

Insert margins to print documents without cutting any phrase

imported pdf's have fixed margins. Frequently I need more room for notes and markings.
Even if a document could be imported onto a larger template page? that would be good.

write without margins is rough.
especially in francophone europe...

is this a planned feature? I'm thinking about switching to an app that has it because of how key it is.

The ability to take an existing pdf (for example a textbook) and expand the margins/page size on that specific page so that you could have more space to write/ take notes in the margins

YES PLEASE. For a note-taking app, this is crucial.

This is a problem for me too. I have posted now a similar idea having not seen your before. Now I have voted for yours