Perfect Resolution - In depth analysis and many questions

MSP430

This topic is to a certain degree covered here by someone else.

In a perfect world (infinite processing power and a high-res display with the needed aspect ratio) the choice of resolution is easy.

Let's say we want to emulate the Game Boy Advance (240x160). We would multiply the resolution with a nice big integer (8) and have resolution that perfectly fits our hypothetical display (1920x1280). We tell our emulator to render to 1920x1280 and our host system to send 1920x1280 to the display.

Pitfall 1:
What is the natural resolution of our console? The Wiki tells us the resolutions of some handhelds:
GBA: 240x160
Game Boy: 160x144
Game Gear: 160x144
Neo Geo Pocket: 160x152
Atari Lynx: 160x102
WonderSwan: 224x144

The consoles for TVs are a bit tricky:
NES:
Wikipedia: 256×224 (NTSC), 256×240 Pixel (PAL)
nintendo.wikia.com: 256 x 240
Stretched to 4:3? Resolution cartridge-dependant? PAL-Version better because of more pixels?

SNES:
Wikipedia: Progressive: 256x224, 512x224, 256x239, 512x239
Interlaced: 512x448, 512x478
Stretched to 4:3? Is this game-dependant or cartridge dependant? Is there a list?

N64:
Wikipedia: Resolutions from 320 × 240 up to 640 × 480
Is there a list of games and resolutions?

PlayStation:
Wikipedia: 256×224 to 640×480
Is there a list of games and resolutions?

Mega Drive:
Wikipedia: Progressive: 320x224 (NTSC) or 320x240 (PAL)
Interlaced: 320x448 (NTSC) or 320x480 (PAL)
HEEEEELP!?!?!?

Pitfall 2:
Shaders. Most people use them. Do they have effect on the "natural resolution"?

Pitfall 3:
Can I get more (valuable) pixels out of the emulator than out of the console?
An example of additional valuable pixels would be the additional pixels when you change the resolution of modern PC games from FullHD to 4K.

Pitfall 4:
The display. Displays do not work with all resolutions. TVs of today should handle:
720×480 (NTSC), 720×576 (PAL), 1280×720 (HD), 1920×1080 (FullHD)
Should be easier for a weak host systems like Pi Zero to render and send the lower resolution and let the TV/Display handle the additional scale-up.
Are there any disadvantages in giving some scale-up to the TV/Display? I guess when using shaders (?).

A lot of questions. Probably a lot of things are connected to taste, but I think most of them are at least interesting from an acadamic/scientific point of view.

lilbud

Most systems that display in 256x224 are stretched by the TV.

The NES' pixels are actually 1.2x wider than tall, probably the same for other systems as well.