I dusted off my previous experiments with Drupal and started messing around. I pretty quickly ran into barriers with the 'out of the box' snap together model, but I see what you mean, the infrastructure could work with some customization.

But, the 'stinking morass' thing gets to me -- maybe better to start closer to scratch w/ e.g. Rails or Django? Why did you decide to go the 'customize Drupal' route?

(for my own notekeeping: brought this idea up again, here: http://news.ycombinator.com/item?id=466673)