I seldom write a nay post. I'd like to think most points are valid. However, the only thing MNK suffers from currently is it's personal skill cap to play. Not only are Monk's capable of the highest DPS production in FFXIV (I've never known them not to be #1 or chasing #1) they are also the most complicated DPS to play from my experience. I have watched many, from T1 to Sepheriot (I've quit a few times between and I've just returned this week pardon the content lapse) Have to be all around more aware, all around more precise, all around more skilled than the other DPS in the group.
Success as a Monk requires a skilled player. When you're running around and you see a Monk with the best gear available, you're looking at an exceptional example of player skill.
I compound this as my person observation. I do not play on a raid heavy server: On my realm only a few of us ever clear the content. (Few being relative to the fact we have had a pretty massive population over the years which recently has dropped sharply while I was away)
By my observations only the best of Monk's succeeded; While I have seen a few mediocre Dragoon's manage some success and glory.