Tiana

I can confirm that this can be accomplished in Publisher V2 (I am on Windows 11). Here are the steps (I am new to forum contribution, I hope my illustration works here...)
Go to the print dialog (I use <CTRL><P> for this) For the printer, select "print to pdf" (red box in illustration). If there is not a pre-installed function on your computer, you can download one. I used "Microsoft Print To PDF", which came with my computer. Select the "layout" button at the bottom (green). Then select "booklet" for the model (blue). You will want to set the paper size, likely double your page size. I am in US, and printing a letter size (8.5" x 11") document on tabloid size (11" x 17") paper. When you click "ok", it will take you to a file save dialog. That said, I have now changed to a workflow where the document is exported to PDF as individual pages. My printer prefers to do its own imposition, and exporting as pages keeps my printed v online versions identical.
I hope this helps!
-Greg

I need the exported layer to remain a specific size for its final use, and by the time I've gone and fussed with positioning a slice, I might as well have just saved the layer by turning everything else off and on again. It would work better for me if I could set the dimensions of a slice, or make it snap to the edges instead of overshooting into the artboard and having to be dragged back into place. However, having to size the slice rather than setting its dimensions pre-click means it's too labour intensive compared to the Photoshop alternative (not that it's worth it to me, I just use Tinytask to record a macro of the clicks and keyboard shortcuts I use so I only have to hit one button to do a few moves). It's useful to know about the slices option but count this as another vote for the feature to export all layers as pngs with a different name, at a specific set size. It is a feature I would use if it were added.

You can do that. Copy a layer and select Edit/Paste Style or Paste FX.

When in the flood fill tool, I want to be able to hit alt and switch to the color picker. I want holding alt to switch me to the color picker in every tool that uses color. When I'm in the advanced fill window picking a color, I want to be able to click on the manuscript to pick a color off of it by default, or by clicking on the eyedropper.

I find this very frustrating. In all other programs I use, hitting x switches the foreground and background colors. That is the only time I want it to happen. A checkbox wouldn't do, because Affinity forgets customized settings for a tool. If for some crazy reason this is a useful feature to someone who isn't me, great, but I want the ability to disable it.

I'm actually a fantasy cartographer myself. I don't have any resources specifically made for Affinity, but any brush sets that come with an image pack, can be used in Affinity too. Way back in the day I made a tutorial, but it comes with a download of fantasy map icons which I converted to a font. Anything in that download is royalty free stock made by me, no credits required. If you follow similar recommendations on DeviantArt you will find many other similar sets which include image packs to be used in any program. There's also KM Alexander who makes brush sets out of historical maps (Popple brush set) and he includes the pngs, so you would be able to convert them to use in Affinity. These are also royalty free, no attribution required. I'm not going to link to them all, just the one, but you can find them by looking through the recommended other sets or in his signature on the Cartographer's Guild, where we both participate as well. It's the most extensive online resource for digital cartography available and definitely the first place I'd look if you mean to seriously get into cartography.
As Affinity Designer is a relatively new program, I can't think of anyone who's made specific resources for them. I'm the only person I know of who's made Clip Studio Paint cartography resources, and as no one's ever expressed interest, I never packaged them up. It's not unlikely in the future I'll make some Affinity-specific cartography packs, and now that I know you are interested I will keep it in mind. I'm a professional cartographer and I am now using Affinity instead of Photoshop and Illustrator, in combination with Other World Mapper and Clip (I just love its brush stabilizer so much more than Affinity's, sorry!). OWM is a program you might look into to build the map base, because it comes installed with a lot of mapping features to automatically do what you want, but it's not free and doesn't do it all, though, so I'm using it in combination with Affinity for all of the photo-finishing techniques I use to push my maps to their final shiny state. No resource kit is enough on its own, in my opinion, without the skilled touch of a designer on top. There are more expensive programs specifically for cartography; I don't personally find them to be worth their subscription fee models so I won't mention those, but OWM is pretty low cost and I've been finding it works really well in correlation with Affinity, quickly becoming my new flow. If you only want freebies, I get it, lots of people do. I have a list of all the free fantasy map generators I could find. Not all of them would be useful for you, but some of them create interesting resources which can be used to reference your original drawing underneath. I made the list with the intent of giving to artistically challenged clients and people who want freebies instead of art commissions, and I think you could get a lot of inspiration from toying with some of them.
Anyway, those are all the cartography resources I can think of off-hand. There's a ton of great brushes with image packs if you follow these leads.
Now that I realize there's interest, I'll see if I can convert some of my resources to Affinity specifically. Let me know what sorts of things you'd be looking for. I have made far more brushes and textures than I have uploaded to DeviantArt, so I may have some I can pull out of my database and share if you can't find what you specifically need. KM's got some real nice hills and trees, so I think you'll be good in that department! But you may find some vacancies. I love making resource packs to share, so yeah, let me know and I can try converting some of my own symbols to be used in Affinity. You do mean as a brush set, right?
Since I'm sharing, here's an infinitely looping wave I just made the other day in Affinity. You are welcome to use it. I haven't released it anywhere else yet. I personally favor the expand, do a stroke, expand selection, do a stroke, expand selection, do a stroke method of coastlines, but this is a repeating pattern fill you could use to fill up water with wave I planned on releasing at some point. If you have any questions about fantasy map making feel free to hit me up.