I make math problems for Math Olympiads for kids, and bouldering feels similar. To build an interesting wall it must not be obvious, but it must be solvable. From time to time I fell in the rabbit hole of a YouTube channel that explain unusual solutions "Beta Break!" by Albert Ok: https://www.youtube.com/playlist?list=PLsfWe31L6Quop7WDY7ky7... (Note: I only climb stair, and only if they are not too stepped :) .)