What is a reasonable number of results I should expect with get_num_queries()? I know it depends on the theme, and I know that smaller is better, but what is a ballpark figure? 10s? 100s?
Depends on the use case. But 100 def. says there's something gone wrong. If you got a lot of custom tables and a lot of different stuff from different tables that you need to display on one page/request, then I'd say 40 is higher than usual. My personal framework does around 10-15(?) queries for a normal blog.