For your input problem, I would recommend:

- disable palm detection completely

- turn off "disable touchpad while typing" completely (`pkill syndaemon` in a startup script)

- use synaptics AreaX settings to ignore taps and drags starting too close to the edge

- tune the tap / doubletap timing

Here are my custom settings for last 2 points:

  AreaLeftEdge 1700
  AreaRightEdge 5100
  MaxDoubleTapTime 180
  SingleTapTimeout 180