The wabi theme is a contributed theme for Drupal. It is recolorable in the style of the Garland theme. It has a few niceties in the look but the layout and look are very reminiscent of Garland.

The Twilight theme looked like it might be a good theme for Drupal. It uses a dark base color with light color text. It can be recolored similarly to the Garland theme.

However once I installed the theme I found there are several layout bugs.

Contented is one of the better contributed themes for Drupal. This is a re-implementation of the Contented7 theme by Tom Rowan. This is a tableless, multi-column, fluid width layout. Parts of the design are ported from the K2 theme.

Nice things are that it does proper layout and it looks halfway decent. It properly handles switching between 2 and three column layout. The color scheme is an orange remniscient of leaves turning into fall colors.

Customizing contented7 is done by copying custom.example.css naming it custom.css and modifying to your choice.

The default theme of Drupal is okay. Garland is much better than the earlier Drupal default theme but it has some, uh, issues. The typical way to develop a new theme is to start from one of the contributed themes and hack it up. ATCK offers a different route in terms of building a theme from scratch.

Instead of hacking up an existing theme ATCK has you use a WYSIWYG Grid Builder service which spits out HTML to implement the chosen grid. That's your starting point.

However I don't like this support and have deinstalled ATCK.