I'm a relatively new Fox player, having played Lucario in Brawl, and switching from Greninja after the nerf, and I play mostly against friends who are semi-competitive, but I've spent the last while trying out all of fox's moves, and find myself using 2132 the most. I consider it the best all-around set.
B2: The canceling of projectiles is great in projectile wars, and the slight stun works well at certain distances to get a dash-grab in. Sometimes I switch to B1 for larger opponents such as DK, DDD, and Bowser, since I can rack up decent damage against slow characters lacking reach. Charizard and Ganon I stick with B2. It seems B2 cancels Warlock Kick.
Dash1: Personally, I find Wolf's much more difficult for recovery from the side, and on an already precise character, making things more difficult isn't a great idea IMO. As well, it is inferior for falling recovery. Falling to one side, and correctly timing a dash to the other side seems to be the safest way to recover, (although shine stalling is fun for mind games and netting grabs). I find with Wolf-Flash, the extra vertical height, and therefore further falling distance makes it possible to be hit with dash attacks from faster characters upon landing.
Up3: I think all 3 Up-B's have their uses, and I think we should have at least one of each on the default sets. Fire Fox has that extra distance, Flying Fox is useful against characters that can gimp really well, and Twisting Fox is really the ONLY one that can be used offensively, while having the same distance as Flying Fox. Personally, I've never had a problem with the distance or startup time, and the ability to angle onto the stage can catch people off-guard. As well, it does a great job of sucking in and keeping opponent's stuck in the attack, whereas people can fall out of Fire Fox. It's definitely possible to use it in a fight in the air effectively, and may be possible to use as a once in a blue moon return-to-stage attack. Fire Fox is slightly better for distance, Flying Fox is better against characters with good gimp play, but Twisting Fox is the best all-around IMO.
Shine2: Definitely the best all-around, as it is the only one that has use against all characters. The windbox can be used against anyone, whereas the hitbox of 1 is mostly useless, and 3 has none, only being good against opponent's with slower projectiles, like Lucario.