The drums!
Okay, the others look hard, and they are BUT
With the drums, she's maintaining height, focus, and keeping the beat, with a single airplane control in one hand sans gimmicks.
(h/t @timminneci)
Specialty control, trick control, etc... This is a control that's not standard but is designed to produce a specific movement.
That's what's going on with the guitars.
Still impressive manipulation, but the control is doing part of the work.
You know those toy ostrich marionettes? That's essentially what she has in her hand. The stringing is different, but it's all about her knowing EXACTLY where her hand is and exquisite control.
These don't.
These marionettists are good at what they do.