Also, your remark about BrM's has little to do with the class and more to do with Sample Bias. There are many more Paladins (competent ones at that) than there are BrM's mainly due to it being a newer class, and a much more different spec. The top paladins, if you look at them, cheese everything with 1 tank fights, now those are maybe 1-5 people in the entire world aiming at those logs, for Brewmasters there are none of those, from what I've seen. It is certainly possible to solo tank those fights to get an edge on the vengeance, but for the most part their guild doesn't care about their "rankings". In terms of AoE, I don't know what Brewmasters you've played with, but when sustained, Brewmasters are still king. About the easier DPS rotation, I don't see Paladins having a rotation that is remotely close to being harder than a Brewmasters, that argument goes only for DKs and maybe Warriors. Tank DPS' main factor comes from being able to get that Vengeance and doing it properly.
Also Raid healing, I don't know what desert your head has been in for the past 2 tiers, or if you've simply been starting at your Recount, but last time I checked, Absorbs count as healing (or does that mean Discipline priests aren't healers anymore). To add to that, for your raid healing to be worth while, you have to give up SoT (which is a good chunk of your "top" paladins' DPS rankings), and use SoI. Brewmasters on the other hand, handle all their smart healing from the damage they do, which scales with the Vengeance they have. They can have both a high amount of Raid healing and a High amount of DPS. That isn't the say Paladins can't, but their Opportunity cost is greater, where as Brewmasters don't have any Opportunity cost between the two variables.
And yes most tanks can eat a Decapitate, you have a personal Guardian Angel. The fact is Brewmasters can do it consecutively for the entire phase.
And yes about your Spirit Kings, its quite funny, the swings are nothing to a Brewmaster. For the most part they could be avoided (85% avoidance much..?) and they can be staggered, which meant they could never killed a Brewmaster, so yes that means Brewmasters could eat every swing as well (Annihilate does less dmg than a single swing so its even easier).