Great choices. People will lament the omission of the Sega Genesis, but that was technically Sega's third console... SG1000, Master System, then Genesis. So your choices for this poll are good. I also believe the answer to this question requires one other aspect.... the second console's actual heyday and it's future influence.
That's why I choose the Xbox 360.
The SNES was the perfect evolution of the NES. It was the 2D hardware that really made the 16 bit era shine.
The PS2 was the perfect evolution of the PS1... a vast library of games, 2D and 3D, a dominant force in the industry.
The Xbox 360 though.... it is the forefather of modern gaming. If you take current sensibilities into account, not nostalgia or the pinnacle of certain eras.... then the Xbox 360 really shines in this aspect. It was a huge leap in performance, ushered in HD gaming, ushered online gaming as a service, and also got ports and remasters of tons of games that came on systems before. It was a drastic market changer for Microsoft in the gaming space, it was the default console for most development of the era, it's online capabilities unmatched, it's library extensive... I got one shortly after launch and the other thing that goes slightly overlooked is how this console EVOLVED. It was like owning a different console completely by the end of it's lifespan.
