Totally ignoring your 6 bullet points... I analyze marathon finisher numbers on an annual basis and look at times about every 3-4 years. Some stats from 2013 (the last year I analyzed) that may indicate courses that are fast - and these are for USA marathons only and are in order of most (or fastest) to least...
10 fastest winning times: Chicago, LA, NYC, Houston, Boston, Grandma's , Twin Cities, Pittsburgh, Quad Cities, Cal International
Most sub 2:20 finishers: Chicago, Grandma's, Boston, Twin Cities, NYC, Cal International, Houston, LA, 26.2 With Donna, Pittsburgh
Most sub 2:30 finishers: Boston, Chicago, NYC, Twin Cities, Cal International, Grandma's, Houston, LA, Philadelphia, 26.2 With Donna
Most sub 2:45 finishers: Boston, Chicago, NYC, Cal International, Twin Cities, Grandma's, Philadelphia, Marine Corps, St George, Columbus
Most sub 3:00 finishers: Boston, Chicago, NYC, Cal International, Philadelphia, Twin Cities, Grandma's, Marine Corps, St George, Columbus
I know, most of these get a lot of sub 2:30/sub 3:00 finishers because they're the biggest marathons in the country. I get that. I'm more interested in the other races that pop up on my list like Quad Cities and Columbus.
A few races on my list that appear slower based on the criteria I look at: Honolulu, Disney, RnR San Diego, San Francisco, Flying Pig, Country Music, Miami, Austin, RnR Arizona Those were all in the Top 25 largest USA marathons in 2013, but all had significantly slower winning times and less sub 2:30/2:45/3:00 finishers than some races with thousands less finishers like St Francis, Vermont City, Eugene.
A few others, lesser known, that continue to pop up on my list: Richmond, St Francis, Eugene