Thank you all for these helpful comments! So, far, the options seem to be:
- Gold Coast/ So Kwun Wat
- Yuen Long
- Sham Tseng
- Tsuen Wan
- Olympic
- Tung Chung (Lantau)
- Discovery Bay (Lantau)
- Ma Wan
- Lamma Island
This definitely gives us a good starting point. We are planning to do what @GentleGeorge said anyway, and get an airbnb/ temporary apartment for the first month or so, so we can check out all these places and make our minds up.
One other thing I probably should have mentioned, is that my wife and I are both women. So we'd want to live somewhere reasonably LGBT+ friendly. My understanding is that general attitudes towards gay people, particularly f/f couples, are kind of OK in Hong Kong, although gay marriage is of course not recognised other than for tax and entry visa purposes. But since we're looking at less urban areas, it's probably something to bear in mind. We wouldn't want to inadvertently move to an area where we'd be likely to get "frozen out" or face a lot of daily hostility.