Pros:
No trouble KO'ing
Has arguably the best Upsmash in the game
One of the fastest characters
One of the fastest faller in the game
Best reflector in the game
Can outcamp most of the cast
Solid aerial game with multi-hits aerials
Best recovery of all the star fox characters
CONS:
7th lightest character
Mediocre at approaching
Mediocre grab range
Doesn't possess any long range attacks
Linear gameplay
Fox is a fast. You always have to move and become fluent switching between camping, aggression, and defense.
Fox is a hard because you have to play risk vs reward. For example: MK at the ledge. You can rarely attack him at all (the odds for that choice are astronomically out of your favor), so you don't. You can't go against your odds. That's why landing with a aerial is impatient choice because the odds are against you.
The principles:
+ Always be doing something even if it's baiting. Constant action, no dead time.
+ Always go in favor of your odds (for example, your opponent in the air are extremely favorable odds: will you go follow up, or run away from him and shoot lasers?)