If you're looking for indie platformers with unique mechanics, I'd recommend checking out "A Short Hike." It's not only charming but also allows for exploration at your own pace, blending platforming with a sense of adventure and discovery. The ability to glide and climb makes traversal feel satisfying, and the little interactions with the environment and NPCs really enhance the experience.
Another one to consider is "Super Meat Boy," which, while it's more known than some, has a brilliant level design that pushes players to master precise jumps and quick reflexes. The juxtaposition of its brutal challenge with a quirky aesthetic is something that I find refreshing.
Have you tried out "Ori and the Blind Forest"? It's visually stunning and boasts a beautiful story alongside its platforming mechanics, which blend puzzle-solving with exploration in a really captivating way. I'm curious what you think about games that mix genres like this.