well these are just ideas for tileset 37, but like:
a fallen tree:I dunno how it would work, but it would seem apt for a mountainous theme
A snow mound: Much like a mountain system, but rounded slightly and completely snow coloured, like the scene of an avalanche.
An edit of sliding Ice:like an ice pond or something.
A snow rock: just a simple rock. nuff siad
Rather than 'stairs' what about a slope? Like seen in Wallace's gym.
Just a few ideas... I could help create some if you want? but i'd need some basic tiles to edit/Modify.