[Save and close multiple files]

Mega-ditto.  I edit photos after a photo shoot.  I might have hundreds of photos that I am editing.  Handling photos one-by-one opening is a deal killer.  Lightroom CC on the iPad allows you to place photos in albums and you can see them in a strip at the bottom of the screen.  When you want to export multiple photos you click on the first one and then shift-click on the last one and you've selected every photo you need.

Affinity Photo seems to have started as being a Photoshop clone and morphed into trying to be a Lightroom clone.  For people like me who work with many photos at once, Affinity Photo needs to adopt more of Lightroom's goodness and innovate from there.