I believe you're missing the fundamental problem of the class, although it might "simpler" in your eyes because of less button presses then those are needed for MNK or NIN.
MNK and NIN are not punished for missing a mechanic or screwing up they continue soar with DPS and maybe only lose out on 5-10 overall DPS for a mistake.
They simply do not need to play perfect and continue to breeze by with amazing DPS
DRGs need to play absolutely perfect to do their DPS and even during a perfection execution of the rotation it comes no where CLOSE to MNK or NIN.
How is it fair that regardless of how well you do, mathematically you'll never reach the other classes? Is that fun? No it's not.
NINs get their ninjustsu every 30 seconds and that is their class defining actions.
Why are DRGs' jumps on a 90s? 120? 180?
How is that fair?
I could continue but just read the topic over; there are fantastic points brought up by others that really delve deep into the problem of the DRG class.
And that is it's simply not up to par of other DPS.
Remember WAR was inferior to PLD in 2.0
Buffed
BLM was "worthless and irrelevant" in SCOB in 2.2
Buffed.
DRG is "worthless and irrelevant" in FCOB in 2.4
???