Hi, yes agree exactly with both your comments.
Eric would have presented himself as exactly what he was, a young man who'd grown up in an affluent household. The British army would I'm sure have been as baffled by the term 'squatter' as I was! I can only think Eric used it because he appears to have been very keen to show he was physically and mentally tough. He took some insane risks during his flying career (OK, you can say that any RFC pilot did that) including volunteering to do experimental night flying without either lights on the plane or on the ground, which surprisingly didn't lead to his fiery death. He also really wanted to pressurise others into taking risks as well -- 'I'll do it, are you chicken?' type thing.
I also think this business of sailing to and fro from Australia two or three times a year, yes, was a strange thing to do, although the (many) sailing lists I've now read through show that it was really common for wealthy Australians. Once in England the Conrans would rent a large country house and take part in upper class activities like hunting and winter sports, demonstrating their membership of that class, I suppose.
So -- 'I'm a tough Aussie but I'm also an English gentleman'?