No offense, but your comment is a perfect example of how listening to customer feedback is more of an art than science. You ask Joel to keep the product simple in the first paragraph and then ask for some non-trivial features in the third. I'm having trouble visualizing both the linked boards idea and what problem it really solves.

The problem with simple products is that everyone has a different idea of what simple means and think their core feature set is what everyone else would want as well.