I'll quote you
I have watched several of those "Let's compare...." videos on Youtube - as it always interesting to see the same game on the different systems to see how they coped, etc etc.
Ahhh, that's one of the highlight about retrogaming. I just love to compare different systems head to head
The extra chips in the NES carts was mostly for memory issues and several different types of bank switching memory were used.
NES was an awesome console for it's time but what inpressed me even more was the quality of the games. Before NES Nintendo released plenty of simple LCD games (Game & Watch) that was incredible playable and fun for being such simple, like Donky Kong for exemple. I remember myself playing Donkey Kong for months every day without getting tired of it. A brilliant idea for a platform game and very playable even as a LCD game. Nintendo was awesome at game design and soon all the big companies as Konami, Capcom, Taito, Tecmo, Irem etc released top game after top game for NES.
Then Sega wanted to give Nintendo a match releasing Master System but were too late. Sega Master System didn't stand a chance against NES and it wasn't until Megadrive was released that Sega could battle Nintendo for real.
Atari's great time was when Atari 2600 dominated the market, Atari was never the same after the 2600 era. Few people bought a computer compared to those who bought a game console instead.
In fact, NES sold more then both Atari 800, C64, ZX Spectrum, Amstrad, Amiga and Atari ST put together.
Shamus is still a fun game that i play sometimes. For me the more "modern" shooters for Atari 800 is okey but the real treasure in gameplay is the old ones such Millipede, Missile Command, Galaxian and Asteroids. Those games is about pure playability and Millipede for Atari 800 is by far my favourite version of this brilliant game, even better then the oginal arcade version me think. So simple, yet so fun to play.