@James - Ahh, agreed. Perhaps we can simply put a recommendation in the install instructions for logo sizing.

@mykz - Also, I'd recommend using cart instead of basket. There are some e-commerce usability studies that mention this as one of their top 10 things. Granted, I believe in the UK basket is used more... so maybe it could be optional. (This does get into tricky issues w/ multilingual sites, though.)

You might also just examine this module as a way to easily add settings to the theme settings form: http://drupal.org/project/themesettingsapi