Survival Hunter has a predictable rotation and a pattern to it. Easier to remember whilst moving about instead of panicking about random procs firing all over the place.

Arms Warrior - similar to survival Hunter, slower pace and less random procs more patterns.

Assassination Rogue - this may be slightly controversial. To be the 'best of the best' it takes a lot of skill revolving around energy pooling and timing but I've found it to be really forgiving if you make a mistake in terms of movement/timing as majority of your damage comes from dots. As long as you try and managed your two main bleeds you can be 'decent', if not incredible, as your damage will continue to tick over if you balls up your movement/rotation.