The main point of my post is: I wonder if there is any way to combine the two views? To provide more background and context, with the necessarily larger numbers of ideas being presented, while still getting useful feedback from readers.

The important thing isn't the idea count. It is how well they are presented in the post and how relevant they are to the audience. Presenting multiple ideas in one post can generate useful feedback however expect the feedback to be focussed on one of the ideas, with others potentially neglected regardless of their merit.

Both Murphy and the nature of online communication suggest that particular focus can be expected on the worst idea, which warrants the most critisism. This may or may not be desirable depending on your reasons for wanting feedback.