Here are a few I watched that I thought was visually interesting:
I like stuff done by PES; you're probably familiar with at least some of them:
The idea of representing objects with other materials is interesting to me. Something like having the sheep's fur look like cotton as an example. I dunno. Crazy idea: having the background look crocheted or cross-stitched. I really like the stuff that people are putting on here.
There would have to be a lot of stuff like this — but if everything is consistent, and there's enough of it, then people could buy it.
Another example of this: explosions are made from bricks in The Lego Movie:
Again, having the bricks be a part of the explosions brings consistency to the world. That idea of using different objects to represent things could be col to explore.
I also noticed some folks mentioning different story ideas, specifically about our mountaineer man. Just to throw in my 2.5 cents/another option:
I personally see him as a world-class mountain climber, someone who wants to conquer the most challenging cliffs just because he can and he's awesome. Ram's Horn has never been scaled before, and he wants to be the first to do it.
When he climbs Ram's Horn, he plants a flag to claim the spot. Cue sheep; they don't like this guy taking their home. When he starts playing with the lamb, the parent sheep freaks out, keeps kicking him off. Mountain man doesn't want to give up, so he keeps trying, but after a while the lamb gets knocked off and... rest of the story. When the man saves the lamb, they both realize that they can "share" the mountain. Cue last shot of sheep on the mountainside with a flag blowing in the background.
I think that having our guy want to climb the mountain so he can claim his spot could be a good motivation for him to keep trying to get to the top, whereas the sheep want him to get off their home. Pretty simple but also clear.