Lets play a game simple game, lets think of a "generation theory", where they decided to include a character from each generation of consoles, you can view these in two ways:
Option 1:
1) Gen 8: WiiU, N3DS, Switch, PS4, XOne, PSVita (Min Min)
2) Gen 7: Wii, NDS, PS3, X360, PSP
3) Gen 6: NGC, PS2, Xbox, GBA, DC
4) Gen 5: N64, PS1, Saturn, GB/C (1996-2001)
5) Gen 4: SNES, Genesis, TG-16, Neo-Geo, GB (1989-1995)
6) Gen 3: NES, Master System, NEC
Option 2:
1) Gen 9: Switch (Min Min)
2) Gen 8: WiiU, N3DS, PS4, XOne, PSVita
3) Gen 7: Wii, NDS, PS3, X360, PSP
4) Gen 6: NGC, PS2, Xbox, GBA, DC
5) Gen 5: N64, PS1, Saturn, GB/C (1996-2001)
6) Gen 4/3: NES, Master System, NEC, SNES, Genesis, TG-16, Neo-Geo, GB (1989-1995)
PC and Arcades can be from any era.
My take (Option 1)
1) Gen 8: Min Min
2) Gen 7: Chorus Kids
3) Gen 6: Sora
4) Gen 5: Crash Bandicoot
5) Gen 4: Doom Slayer
6) Gen 3: Ryu Hayabusa