why are you encapsulating everything in lists for your yaml example? you arent in your other examples either?

    - filters:
        - operant: =
          type: user
        - operant: =
          title: nick

if the module author wants to, he could even remove the secondary list because its the same operator, making this

      - filters:
        - operant: =
          type: user
          title: nick

thats just as readable as your other examples imo. yaml doesnt have to be an unreadable mess. its just possible to make bad apis, which remains true for yaml just as for any other format.