I've been thinking about this for a while, because I don't like how the winter mode works currently.
The goal is:

• Grass blocks should not be replaced with snow blocks, but should be covered with snow layer above them, just like most objects.
• Roads should not be covered with snow, maybe except some minor roads without solid surface
• Water should be either replaced with ice or removed (in artificial objects like fountains)
• Minor plants like grass and flowers should not be generated, but replaced with snow layer instead
• The code has to be clean, fast, reliable, and compatible with adding new features

The first small step for this was already done by me in #403, now in winter mode there are dirt blocks covered by snow layer blocks on farmlands, water in farmlands is frozen, and most lakes are frozen.

This discussion was created to talk about the best way to implement this.