Strava has new maps. They look good and they are well-designed. Highways, which dominate normal maps, have gotten a modest grey colour. Paths and pedestrian areas are highlighted in yellow. Parks and water bodies serve as orientation marks.
They have removed clutter so you can easily follow the road pattern. And they’ve taken care to make elevation patterns visible (too bad most hills in the Netherlands are too low to qualify for such markings).
Hopefully the new Strava maps will become available open source for use with Leaflet. Or for your Garmin.
23 July 2018 - I’m still very happy with the Strava maps Mapbox created. I do think one thing could be improved, though: railways are almost invisible unless you really zoom in.
Of course, this is in keeping with the design philosophy of the maps. On the other hand, motorways are clearly indicated, so why not railways. Adding railways and stations would improve the readability of the maps, especially in large cities. It would also add practical value to cyclists who take their bicycle on a train.