I’m constantly switching between Gnome and KDE (Bluefin, Aurora, Bazzite, Kinoite, Silverblue, whatever) and I never had any issues.
The only thing that gets messed up a bit is theming, where I have to change the GTK theme, and sometimes the window buttons when I go from KDE to Gnome, which is also reverted in just one click in Gnome tweaks.

100% AMD, for sure. AMD won’t make much problems and works ootb.

Nvidia on the other hand… if you already have a Nvidia GPU, then the proprietary drivers work pretty well, but even those won’t work flawlessly and still cause problems for many people.
And the FOSS drivers are still in the early stages and won’t cut it. So why spend lots of money for a piece of hardware that won’t give you the performance you paid for?

Also, Nvidia clearly doesn’t care about PCs or its’ users, so why support such a shitty company with your money?

1. Distro choice

I would recommend you either Aurora or Bluefin.
Both are pretty much the same, but differ in their desktop environment.

Traditionally, Gnome (Bluefin) always has been the champion in terms of being tablet-like, but from what I’ve heard, KDE has surpassed Gnome in terms of how well it works as a tablet UI.

You can install the one or the other, and then later “rebase” to the other variant without needing to reinstall anything if you want to try the “competitor” or if you’re unhappy.

This basically switches out the base system, but your installed apps and pictures are decoupled and kept. Like just doing a big update :D

Why do I recommend you exactly that, and not just base Fedora or Kubuntu or whatever?

Simple - you need to install the linux-surface kernel (and stuff), because without it, nothing will work, no stylus, no sleep, no battery, basically nothing.

But said modified kernel is nothing ordinary, and might shit itself randomly.

Not only would you have to install everything by hand, which was a task that not only let me return to Windows once, but twice as Linux noob! It also causes a lot of headache when you have to spend your evening fixing it via CLI or whatever.

Here uBlue comes handy: you can “fix” your system with just one click.

• Smort silica rock not thinking?
• Grub says “NØ” after system update?
• Me not care, me pressing space while booting, me selecting yesterday image, me watching YouTube when eating because me don’t care, knowing that dev daddy is already working on fix that ship tomorrow.

You don’t even have to do manual updates or whatever, everything is done in the background for you, just like on your smartphone.

You have to select the “I have a Surface device” option, and then everything comes pre-bundled and (hopefully) just werks™

2. Note taking and PDFs

I don’t know 🤷

3. SD card

🤷

4. Stylus

I believe KDE is better, because it has many wacom tablet input settings and features, but I sold that crappy Surface ages ago when Gnome was the obvious choice. The 🤷 also applies here I guess, because it was two years ago and felt like a completely different age compared to today.

I recommend you doing so, but not as a security measure, more of so as a “keeping everything organised”-measure.

I like to keep my host OS clean and install everything containerised

You did everything right. Boot into the image that works, and then apply rpm-ostree rollback. This reverses the broken image and the working one, so you’ll boot into this one the next time you boot up until you change something in the order, e.g. by updating.

In the meantime, wait a day or so and then update again.

On what channel are you on? bazzite:latest or bazzite:stable?

If you’re a fan of that principle, then consider checking out Logseq.

It’s main workflow is that you use the Journal page and write down everything that’s on your mind, may it be projects, research, social stuff, or whatever.

And while writing, you link that stuff with other stuff, and in the end, even when forgetting the exact search cues, you can go hunting for words mentally, and always find what you wrote months ago.

Obsidian, the competitor of it, is also great, but more similar to traditional note taking software, and therefore more hierarchical.

Logseq is FOSS too btw!