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.