Finding good minimalist base themes I am working on a Drupal project and teaching myself the system as I go along. I am trying to find a minimalist theme to use as a base for developing this site. I don't want a framework, because I don't have time to learn that too. I really just want a minimalist theme that looks good out of the box, but that can be easily modified in basic ways.

In my experience so far, most Drupal themes are either overly designed, or completely lacking in any formatting whatsoever. In the WordPress world, there is (for example) something like Thesis, which looks good out of the box but also has lots of potential for modification. Another example would be WooThemes' Canvas. Is there anything similar in the Drupal world?
Zen is all right but after using it a while I ran into problems since it's not built on the grid system. I found Omega pretty amazing as a grid-based starter theme for Drupal 7 with a responsive option. The steep learning curve was worth it, and it provides great tools and help.