GB wrote:

Have you considered having a raised patio where you can sit out at the
same height as the house floor?

I have, yes, though the back door isn't the only access from inside the
house to the garden: there are also patio doors from a different room, so a
floor-level patio adjacent to them (either in addition to the back door one
or instead of it) is also a possibility.

I like the idea of a same- (or almost the same) level patio, but the height
of the interior floors might give a matching table-and-chairs area an
uncomfortable view into my neighbour's property even over the six-foot fence
which separates us.