So which Screen Protector do you guys recommend if the priority is to have the best possible image quality on handheld mode? Price shouldn't be an issue (unless it's something crazy like 100$ or something)

dont knw the brand, but pick the glass screenprotector. Some ppl reported that the heat from switch caused some plastic screenprotector to peel off

Does it not reflect the light too much or wash out the image?

I dont see noticable difference on my phone. You may want to purchase from well known brand

The front of the Switch Dock looks like it can be broken off pretty easily, maybe people can modify it that way?

I recommend Hori for screen protective film.  They have a standard and premium version for Switch.  Standard has always worked just fine for me.  They go on nicely and I cant even tell it's there.  I call crap brand protective film or total bs altogether on the film peeling.  Switches "heat" output is quite low, and I've had Hori protectors on my original ds, (3) 3ds, "U" and now the switch.  The older ones are still stuck in place as nice as the day I put them on.

The other thing to note about this "horrifying" screen scratching possibility (if it even truly exists, which I do not see a way it can with the unit I have) is that if you look where the plastic rails are in the dock, they don't touch the display area of the screen anyway.  It's against the black bezel around the side of the screen where they rest.  There shouldn't be any way of the dock itself scratching the viewable area of the screen.  /shrug

Here is a decent vid that covers the Switch durability...other than him not dropping it, which I don't know why he didnthttps://m.youtube.com/watch?v=XJP6gERPmMk

https://www.youtube.com/watch?v=kqMgv9hHmrY   ...and here's a drop test.

For those curious, here's a good screen protector.

https://www.amazon.com/Nintendo-Switch-Protector-amFilm-Tempered/dp/B01N3ASPNV/ref=sr_1_2?s=videogames&ie=UTF8&qid=1488833929&sr=1-2&keywords=switch+screen+protector

very nice to see someone actually use mineral hardness testers

scratching at Mohs 3 means the used material is just a bit harder than finger nails, so it's pretty prone to scratching especially as several types of particles that are common in regular dust are harder than that