An orchard would be a wonderful addition to this theme, many medieval and Tudor gardens were simple parterres next to orchards. Another theme is the edible garden. This is also very well suited to the theme of parterre and orchard. It can include an arbor on which to grow grapes or kiwis or even gourds, with fruit trees espaliered along the enclosing fence. An herb garden can be a wonderful feature in an edible garden.
Country gardens can be a theme.
The manor house garden is a form of country garden, but I think of country gardens as unpretentious. Domestic animals can do a lot to maintain a country garden theme. The edible garden and the cottage garden go perfectly with this theme. Light colored gravel paths, especially straight ones, show up very well in the moonlight, are very easy to navigate. If the garden is designed for moonlight, it will probably also feel unified under sunlight.