Why is the Image Sensor Board routing different?
As Answered by the Elphel Maker Andrey


  The 45 degree directions were made by the ancient software that could
  not work with arbitrary angles. Generally parallel traces have more
  crosstalk than the ones with "random" angles. Except, of course
  controlled impedance differential pairs, but they are parallel only to
  each other, and not to the other pairs.
  
  All modern boards use random angles where possible.
  
  Andrey