A markedly different UI is that of FutureWave SmartSketch which has been reimplemented in

https://www.wickeditor.com/

For Beziér curves remember the basics:

- put nodes at extrema and points of inflection (extreme left/right, top/bottom, middle of _S_ curve)

- rule of 30 --- off curve nodes should be ~30% away from the matching on curve node for smoothest appearance unless the shape one is trying to achieve dictates a different placement