["Select Same" and "Select Object" with multiple artboards]

Another vote from me for being able to limit the selection to the active artboard. The only way I seem to be able to get around this is to copy the artboard I want to work on and put it in a new document. I could definitely see how being able to BOTH, select all of a type from the entire document, or limit it to artboard/group/etc could be very useful! Please put this feature in a future update Affinity! :)

[Updateable snapshots plus being aware of embedded docs state]

Yes, please update them to remember what layers are on/off! This is what I primarily use Layer Comps for in Photoshop, it's a major part of my workflow.

[Vectorial sculpt]

Yes it would be great if there was a "sculpt" mode, where an existing object could be selected, then with your brush you can push and move around the nodes with a fall off radius. Basically similtar to a Liquify but for vectors, and different settings to control the fall off.

[Simplify Paths]

Another vote for this feature! Would be so helpful!

[Auto Select Layer]

Another vote for this! I use the "Auto Select Layer" feature in Photoshop all the time, I turn it on and off as necessary. It's extremely useful!

[Layer comps - Layer comps to files]

I would love this too! Easily switching between, updating, and using Layer Comps in Photoshop is an integral part of my workflow. I use it so often, along with exporting "laying comps to files". I honestly need the feature..so if Affinity Photo gets it, I'll probably be making the switch!