I interupt your fierce debat to bring you this common sense!
Boy the Falco people and Wolf people sure get rowdy at each-other. Allow me to rant at you:
Characters are more than just representatives of series, they showcase their latest/greatest game in the "festival" that Smash Bros allegedly is. It isn't necessarily all about 'significance to the series'.
As for the 'clones dilemma' at this point, people are just looking for excuses. Nobody is going to make clones of anybody. For SSB64, the development didn't have anything to base a moveset on, so they made something up. This time around, after the release of both Adventures Assault and Command, the development now has a few more than 2 games to look at for reference. Krystal is pretty much in, and most likely with her staff, thereby adequately representing the Adventures part of the series. That leaves Assault and Command. Command doesn't have ground combat as far as I know, which leaves Assault. Using elements of Assaults ground combat as a guideline, the development can create a unique moveset for an additional StarFox character. Naturally, this niche would be filled by either Wolf, or Falco or both.
Having four representatives from the Starfox series is not inconceivable. The Kirby series has three as of now, and last time I checked, Kirby was well below the Starfox Series in overall popularity, sales, and recognition. Mario has five (Counting Wario) with at least one shoe-in: Luigi. The Zelda series has 2 as of now with at least one shoe-in: Ganondorf and several possibilities for additions. Four representatives are reasonable, but of course we being human and thus inquisitive, have to ask "what if there's only three?". being human and thus competitive, we must prove our own point right as to who gets the coveted 'Third Spot'
Trying to compare Falco to Wolf and deciding who is more important to the series is kind of pointless. The 'best friend' character and 'rival' character are like two different but necessary components to machine. Its like trying to decide if a Spark-plug is more important than a wheel in a car. Falco and Wolf are both important ok? The series wouldn't be right without either of them.
That concludes my rant. You may now resume your finger-pointing, bickering and flame throwing.