Genghis
(1) I see and having had a look at your route there was no reason too.
(2) Agreed, but with hindsight most commercial control zones (perhaps sadly) are less inclined to do "jobs" on the land line for us GA pilots. I am not sure I completely agree with my own point as I personally have always found Solent really helpful but I know that is not everyones experience.
(3) I suppose it depends how you use the radio. Personally I am a bit of a radio freak. I feel it does no harm at all to tell the nearest radio what you are doing because any information they can give you might be of help. For example in bound aircraft will probably give them a call from some distance away so that helps build a picture of who is around, they may know of aircraft aerobating in their vicinity and they may know of any temporary restrictions (which yes of course you should have got from the AIS, but might have just "overlooked"). I equally understand that there are others who prefer to avoid speaking to anyone if they possibly can.
If you did go to Selsey or somewhere in that vicinity and then direct Popham you would have routed somewhere around Thorney island. The fact of the matter is solent isnt interest in traffic that far away from them and nor is Shoreham. That is very much the local flying area for Goodwood though. They often have aircraft aerobating over Thorney island and a lot of aircraft routing east along the coast will give Goodwood a call before Shoreham.
So I suppose I am merely say Goodwood might have been worth a call and certainly would have got on the land line for you.