I think Starfox 64 is one of the top five games from its era. The difficulty levels of progressing through the planet system different ways (three base paths with warps and transfers between), beating bosses/planets different ways (there's almost always a "fast" and a "slow" way, plus entirely different bosses in some cases), the Pro mode you unlock when you defeat the final boss at his hardest (this really changes the game--more enemies in new places, plus Fox gets shades like his father), the storyline changes that can occur based on your performance (a later level blows a fin off of you mothership if beaten too slowly, which stays gone in all cutscenes thereafter for instance), the relatively great graphics, and the level of skill you can develop in the game...man, I'm going to have to emulate this one for old time's sake. I can't recommend Starfox enough. The first one was ahead of its time and suffered graphically, but 64 was a swan song of its generation.
Starfox shows a level of completion and enjoyment in single player that most games only approach in online multiplayer, especially for shooters--which almost never have multiple endings or stage paths. It's right there on par with Goldeneye. Play it, and if you don't like it, I owe you an Arwing.