I like PT John's rankings pretty well, but they're definitely up for debate. I think Zapdos is probably the hardest to place and Snorlax is the easiest. Zapdos doesn't look top-S rank, but between middle and low there are a few things.:
Why it could be middle:
--The most versatile mon in the tier.
--Offensively, only Mienshao has it beat in off-the-bat strength.
--Great speed and balanced defenses let it serve as a utility counter and also provide offensive power to the team.
Why it could be low:
--Stealth Rock-weak.
--Can't sweep quite as threateningly as the rest of S-tier, unless it runs Agility, in which case it sacrifices its early-game utility.
As for Snorlax...
--It defensively at least checks roughly half the tier, irrespective of the set it runs.
--It hits incredibly hard when equipped with a Choice Band.
--It is the best phazer in the metagame.
--It's a threatening sweeper on offensive and defensive teams, breaking walls early on in the former and walling early game and working as a comfortable win condition in the latter, even taking the strongest Fighting attacks at +1 Def.
It's the best defensive poke in the tier and excels at all the roles I mentioned above, and it fits very easily onto teams.
Why it could be middle:
--The most versatile mon in the tier.
--Offensively, only Mienshao has it beat in off-the-bat strength.
--Great speed and balanced defenses let it serve as a utility counter and also provide offensive power to the team.
Why it could be low:
--Stealth Rock-weak.
--Can't sweep quite as threateningly as the rest of S-tier, unless it runs Agility, in which case it sacrifices its early-game utility.
As for Snorlax...
You're going to have to provide a better justification to rank Snorlax lower than top-S, because "fighting weak" doesn't cut it. All of the other Pokemon in the S tier are easily KO'd by multitudes of moves on the opponent's team, while outside of Escavalier's Swarm-boosted Megahorn, a high-powered physical Fighting move is the only thing that can OHKO even offensive Snorlax 100% of the time-- and that doesn't even cut it if it gets a Curse boost. I think it's hard to argue with Snorlax as the best Pokemon in UU for these reasons:As for the top-mid-low Rankings, Snorlax doesn't deserve Top S-rank. Almost every team has a fighting type who can easily KO Snorlax.
--It defensively at least checks roughly half the tier, irrespective of the set it runs.
--It hits incredibly hard when equipped with a Choice Band.
--It is the best phazer in the metagame.
--It's a threatening sweeper on offensive and defensive teams, breaking walls early on in the former and walling early game and working as a comfortable win condition in the latter, even taking the strongest Fighting attacks at +1 Def.
It's the best defensive poke in the tier and excels at all the roles I mentioned above, and it fits very easily onto teams.