In my experience, the "complicated" rotations don't necessarily come from the rotation itself, it's trying to keep up the rotation to maximize damage output while adhering to mechanics. WoW mechanics do the same thing sometimes, but in FFXIV it's very common for mechanics to be heavy for 5-10 seconds at a time, in which time your procs or combo buff could fall off and throw off your rotation.
It's the same in WoW as it is in FFXIV in this respect...knowing the battles and prioritizing cooldowns and knowing when to let loose and when to hold your damage a tad is what separates a "good" player from a "great" player.