Would it be possible to select how Photo/Designer open PDF files?
I often use PDF Plots from Autocad as a base for a drawing that will then be rendered digitally (hand/tablet drawn landscape plans over an architect's base drawing). In the dreaded photoshop the PDF will open as a raster image with transparent background and is quite quick to get going. Affinity's intelligent opening of these same PDFS and recognizing their vector content can actually be a bit of a bind in this instance as I then have to go and group layers and such to separate the printed data from what I am going to add.
In many instances the current behaviour is beneficial and should be kept (ie DTP usage), but perhaps a flag on file import/open to rasterize on import could be implemented? (I have found sometimes I need to use designer to "flatten" the image as photo does not want to do a whole stack of layers).