The one trick I've found is to time your starter around when you start the loaf. As a starter develops, it goes from yeasty to sour. So options can be:
Refresh starter, wait for five hours, then start the loaf with it- results in a milder flavored loaf
Refresh starter, wait 12 hours- Sourer. This is how I like mine.
Refresh starter, wait 24 hours- Very sour.
You're right, though, that Tartine process is a commitment. I've streamlined some of it (a much shorter bench rest, and doing a shorter final rise), but it's still an all day process.