I do agree that Knuckles without Tails would feel incomplete, but honestly I think that's just my Classic bias kicking in. I see it kinda like... imagine if Peach was in Smash 64 instead of Luigi for example, the lack of Luigi would be weird, but it'd be understandable as to why they rejected him - sure, Luigi has been playable more; but Peach was overall more important to the Mario series at the time, especially hot off Mario 64.
The same goes for Tails and Knuckles, Tails has seniority, better "brand awareness" and a high amount of playable roles, but Knuckles is generally the more popular one and has more importance to game plots for the most part. Either would be an equally as good choice really, but in teams of pleasing fans Knuckles seems to be the safest bet.
The same goes for Tails and Knuckles, Tails has seniority, better "brand awareness" and a high amount of playable roles, but Knuckles is generally the more popular one and has more importance to game plots for the most part. Either would be an equally as good choice really, but in teams of pleasing fans Knuckles seems to be the safest bet.
I also think since Tails’s moveset would probably be very basic, Tails feels more like a newcomer who should have already been in the base-game, unlike someone like Eggman