It was a couple of years ago I laid out this terrain, but I recall I was trying to keep the number of SPs down. I think many terrains have too many, which dilutes the GV action and encourages milk running.
Having said that, I can see no reason not to put SPs to the island airbases from the ports. I imagine if CraterMA is ever used by HTC it won't be before the next version of AH comes out. After that I will have to modify it for the new terrain so I can add the extra SPs then.