Ranking of classes based on simplicity?

The question for the most 'simple' class I know gets asked quite a few times, but I'm curious to see how the overall classes would rank. By simplicity I mean in terms of rotation, not a lot of spells having to be used (like sub rogue requires quite a few cooldowns to track) and generally a class you can play when you're exhausted at the end of the day and just want to play something that doesn't require a lot of thought and tracking (like ret paladin or perhaps zug zug warrior?). APM can go either way as I know some folks prefer less stress on the fingers so that aspect is probably subjective.

I imagine BM hunter/Ret Paladin/Destr Warlock would rank at the top) while Sub Rogue/Fire or Arc Mage/Feral Druid would rank at the bottom. How'd you folks go about the ranking?