Create a Global Heatmap for Mountain Biking data only
I'm absolutely in love with labs.strava.com/heatmap/ - however I would love it more if I could see a separate heatmap for mountain biking as for road biking. Mostly I want to see where I can go with a road bike, and what routes would be more interesting for a mountain bike ("avoid roads").
Thoughts on implementation:
The simplest: if enough Strava users accurately mark their rides as being by road bike or mountain bike, simply generating heatmaps from the tracks marked as having been ridden by mountain bikes and one for those ridden by road bikes could do the trick.
With insufficient well-marked tracks / bicycles (i.e. if there's a data quality problem), more magic would be needed. I want a heatmap that is road bike friendly, and a heatmap that indicates where I can go that avoids the roads that are roadbike friendly. :) So any way to subtract one from the other would be useful. This is related to feature requests wanting segments identified as road bike or mountain bike segments, that might be a reasonable starting point. Once segments are reasonably well identified, one could use them to guess what kind of bikes a cyclists often rides.