Hi Neil, so this surface is planar so that's probably a good one to construct first from planar profile curves:



Then this area here:



I'd probably try making an extended sheet something like this using Sweep or Network:



Then that would get trimmed by a profile curve like this:



And then these areas would be done with a Construct > Blend.



You could get a large portion of it built like that but then the rounded tip protrusion like spots will be the most difficult to do well.

- Michael