When Mapquest layer disappeared, this was a problem for OpenSnowMap: its cold colors and less detailed style were great to overlay ski pistes onto. But the end of this freely available map forced me to build a simple style with plenty of room for ski pistes: the OpenSnowMap Base Snow Map.
A winter topo map
I used OSM-Bright to start building this style. Using colder colours more suited to a winter map, of course I also added relief. In particular, relief hillshading led me to desaturate highways to avoid they pops out the shadowed side of the hills .
Ski pistes are not rendered on this layer, the OpenSnowMap remains an overlay. In fact, they are rendered on the Base Snow Map with 12 pixels wide transparent labels that forbids other labels to take place where ski pistes from the OpenSnowMap overlay will land.
I want to see it!
This style is only showcased on http://beta.opensnowmap.org for now. The mobile part of the website is shown with 'retina tiles' by default, but you can choose this high-dpi option or not from the menu.
For these mobile-friendly tiles, I choose to render 384px tiles and display them with a 1.5x scale factor. That please my eyes on my own phone and the server seems to be OK with them, so please tell me they also looks good on your phone or tablet.
Of course, Openstreetmap-carto is still available, although without high-res tiles but a simple scaling for the mobile version. Here also let me know what the default should be: I find it more usable with the scaling on my device, although a bit pixelized.
That's great, but ...
Unfortunately, the use of the layer outside OpenSnowMap will be discouraged by referer magic and so on. Also, tiles containing ski pistes are pre-rendered, but not the others. So while the Imposm-powered DB is up-to-date and a few minutes behind Openstreetmap, don't expect super-performances in tile refresh. Yes, 10 minutes so you can check your mapping mistakes and correct them before I take them into account, isn't it clever ?
This new base map won't change much the OpenSnowMap overlay tiles that will remains pretty much the same and updated daily.