Drupal Style Guide
When in doubt, check out the Middlebury Editorial Style Guide for usage questions: how to type a phone number, what to capitalize, etc. You'll find the guide here: http://www.middlebury.edu/administration/communications/info/
Use as few typefaces as possible. For most of your text, use the regular paragraph style, and select just one or two display (headline) typefaces.
Avoid long banks of type when possible. If you must have a page with a lot of type, use lots of subheads.
Use display (headline) faces sparingly, and never for lengthy banks of type.
The "opening paragraph" style should only be on the home page of your site. And since it's designed to appear below a banner which includes the name of your department/office, you don't need to use a headline on top of this.
Don't use the "opening paragraph" text for more than (ta da) the opening paragraph, and don't let that paragraph go on for more than three or four lines, and never more than six.
Don't use images as decoration. Images should be chosen to accomplish something specific.
Make sure images are of reasonable quality, and sized appropriately. (No huge head shots! No tiny panoramas!)
To display a large number of images, use the photo gallery content type.
The "juice bar" feature is a convenient place for sharing stories about your department or office, but remember that it takes up quite a bit of space at the top of your page. Laptop users, without scrolling, will see the main navigation, your banner and the juice bar, and that's about it. So, use the juice bar only if you have something important to say that can't be handled in any of the other content areas.
Pick a color palette you like, and then stick with it for your entire site.
Check out and follow the advice from White Whale's Janie Porche on what kinds of content to use on different parts of the page.