Don't think of it as a rotation. It's a Priority system.

Ninja and Monk have even longer Priorities.
Really, but I remember over the months since 2.0 from various forums and dragoons in dungeons saying that dragoon was the most complicated of the jobs to play. If I treat it like a priority system, similar to Smn, it becomes simpler while still being competitive?

I've had a pretty fun time switching it up with MNK and BLM recently, but I'm still a DRG player at the core.

There's no harm in checking out the other classes to see if you like them or not. You can always go back to DRG if you don't.
Under normal conditions I would do that, but to do so currently means I have to level up Monk and Ninja and at the moment my Monk is level 39 and Rogue is 22 and I've yet to get more than one dungeon a day with them, so I usually give out since the remaining options for leveling them tend to feel very boring to me.