We went through the appeals process. It was very unhelpful. I got the impression that until we responded "we have updated the application", any objections were routed to the same unreasonable person that rejected us originally who didn't care to look at the same application twice.
We ended up adding a "feature" in a completely superficial way. We took an existing feature of the application and we exposed it as a top-level menu item instead of making it appear in the context where it makes sense.
As soon as we told Apple that we'd added a feature and they could verify that there was a new top-level menu item on the first screen of the application, they approved it. It was essentially the same application that they thought didn't have enough functionality, except rearranged slightly to make the functionality obvious to a reviewer that doesn't look past the first screen.
As far as I can tell, there's a lot of pressure inside Apple to churn through reviews as quickly as possible, and the review process is getting sloppier. Things get approved when they have glaring faults, and things get rejected because they didn't make a good impression in the first few seconds a reviewer looked at it.