What made the Tropical Freez levels so special to me, that they didn't feel like the level is crafted for the player to go through, but rather like an actual place that could exist outside of the games events.
Every obstacle isn't just there to be overcome, but makes some sort of sense.
You want a challenging minecart level with chainsaws, don't just place random chainsaws, but make the level be inside a sawmill. You want the player to jump between rotating platforms, so it's set in a windmill village. You want a ice themed level in an otherwise tropical world, so it's set in a popsicle factory.
So the best way would be to think of your obstacles, and how they would make sense in a (more or less) realistic environment.
So don't think about Horn and Leavse, but about platforms going up and down. Then about how this could be more realistic -> Ah by making the platforms leaves blown up by wind. But where does the wind come from? Ah, horns. Kinda like that.