Well, a Drupal architect can be quite a few things.
While the architect often works as the "layout editor" for a Drupal site, this person is usually also deeply invested in a site's information architecture and how to build features that help a communicator create their content more efficiently. Architects work with developers to help provide programmatic specifications and feedback on the functionality of a module or feature. Architects will often both conceptualize and build features.
While an architect is definitely interested in the style that content appears on a site, we're typically more involved with the method in which content is delivered. Typical quetions that an architect asks, and answers, on a regular basis are:
Architects are interested in both helping a site's audience effortlessly find what they're looking for while making it painless for a communicator to get their information in the system in the first place. As a result, architects spend a lot of time with structural elements in a Drupal site such as Taxonomy, Menus, Fields, Pathauto, Display Suite, Webforms, and Views.
If you've got an interest in any of the above, then you've found the right place! Welcome to Drupal architecture. :)
Image courtesy of Enrique Herbella, "The Critical Importance of Google-Friendly Website Architecture", EntrepreneurWeb. 2013-06-13, 2015-07-22