Having thought about it, my guess for the 9 strongest systems goes:
SNES
PS1
PS2
N64
Switch
GB
NES
GC
DS
With the GBA, Wii, PS3 and PS4 lurking on the periphery. PC is a wildcard.
I would resist the urge to balance this list out with non-Nintendo systems - the Genesis and 360 are not gonna have the juice. Nintendo systems have by far the strongest legacies, especially on GameFAQs, and they're gonna dominate the entire scene - only the PS1 and PS2 are big boys compared to the Nintendo stuff. PS3 onwards lack the lasting brand power to be better than a midcarder imo.