Alison, your simplistic approach is a good start. You are also correct when you say the page content and the template should be separate. Essentially you have a layout, template, webpart zones, webparts, page types and documents. You create a layout with webpart zones and use that in your template. Inside your template, you add webparts and/or widgets to your template in the zones you created in the layout.
In the webparts you can then define content you want to display. For example a list of News items. Say you have a page in your content tree /News. Under the /News page you have 10 news items (each is a News Page Type). On your /News page you define the page template and add a repeater and define the page types you want to display, how they display, if you want them to be paged, etc. Now all your content editors do is add new news items in a form, vs in an editable text area. Using Page Types also allows you to utilize the content in other places on the site and possibly other sites within the same Kentico instance.
Kentico is build around using custom Page Types. You can create these page types in the UI very easy and give your content editors a simple form to enter data in. Then in transformations, you display that data in the format that has been dictated by a designer and implemented by a developer (or savvy content editor). Page types are linked with documents meaning they will have page relevant information (url, meta data, etc.) with them.
Hopefully this helps out a little, if not, look me up and I'd be glad to help out.