Just got back from a long day away from the desk, will look at this tomorrow.
I'm thinking a good default would use the default templates (as they are good), memcached, PostgreSQL, have a config file in /etc (because no-one should be hard-coding their app, even if it's a quick thing) and I'll make some excuse to include the scheduled tasks as there is always an edge case need for them. I won't try and solve user login, I'll just use Persona.
It will be basic, but have a lot of simple components that people can delete out or extend depending on what they want to do.
Hah, not yet... this is really quick prototyping through to deployable something.
Once I've put it up, I'll accept pull requests... I'm sure there's enough people with small reqs that it could be knocked into shape enough to show how to do most things.