You must not have actually played the games, then. Falco did not leave at the end of 64 - no one did. At the beginning of Adventures it was mentioned that he had done so between 64 and Adventures, but then he returned at the end of Adventures. The entire team then split up before Command, but in most of the paths of that game Falco also rejoins, and a number of the endings have the team staying together (one even has Fox and Falco becoming F-Zero racers, weirdly enough). Heck, even the ending where Fox's son forms a new Star Fox squadron has Falco among the new team.Alright, Wolf and Falco's roles in the Star Fox series are suddenly changing.
I believe in StarFox 64, Falco left the Starfox team. Although he came back in Assault, I think him and Fox's relationship as BFFs was coming to an end soon. Wolf, on the other hand, has become more of a friendly rival as the series progresses, teaming up with Fox to battle a greater evil.
If Smash 4 comes, I'm expecting Wolf to stay and Falco to go.
And Wolf is not becoming more friendly. He does what is in his best interest is all - when he and Fox share a common foe, he will reluctantly assist him, as is the case in Assault and some Command paths. In 64 he was employed by Andross, so it was in his best interest to fight Fox. Nothing has changed between them - they're still rivals with a dislike for each other but a grudging respect for each other's prowess.
Zevox