Please share,I think the chairlift data is the most important , it will show the shape of the mountain. The route down and speed don't really matter.
One stat I love to look at is average speed for the day... I mean I tend to ride the same speed down wherever I am, so a higher average speed means I'm standing in lift lines less, and riding more high speed chairs.
Another stat I love is vertical meters / total distance. Garmin doesn't work this out for you, but you can quickly divide it yourself. When somebody says "Sunshine is all cat tracks and flats" I can show them with GPS data whether this is actually true or not. More vertical per horizontal means the hill in general has less flats.
So far GPS has told me that I get by far the highest average speeds at Nakiska. All the lifts are high speed, there's rarely a lift line, and the grooming is really good so I'm able to blast off laps. I also tend to set my highest vertical / distance numbers there, as I tend to ride the "gold" chair which is pretty much up hill on a 20 degree angle or so the whole time, very little flat at the top and bottom.