Great post Sarah :)

Data portability is one of the cornerstones of our development strategy and why anything non-theme related is being built as a plugin.

To deal with the setup fatigue, we're also working on a plugin that will allow for one-click download and install of both the theme (+ child theme) and plugins.

One thing we've been thinking about a lot though, is that it would be much better if this was a community effort.

1.) 100% WordPress native - it should look and feel like a natural extension of WordPress.
2.) Only enough functionality to fulfil it's purpose - any additional functionality available via extensions.
3.) Easily extendible via hooks, filters (and more) - making it really easy for developers to extend or build 3rd party extensions.
4.) Not overloaded with configuration options - built for the content creators (ie, the people using the site).
5.) Built with performance in mind.

Assembly looks like the perfect platform to collaboratively build out the base plugins.

If anyone is interested in getting involved, please send an email to chris[at]themebutler.com.

We will be reaching out to other theme and plugins devs to see if there is any interest in a collaborative effort (Justin Tadlock being at the top of my list).