There is nothing overkill about MVC. It is far simpler than webforms. Webforms is the one that is overkill. The massive view state object that is serialized with every request, the fact that it tries to emulate windows forms controls with heavy objects and non-HTML tags. You want HTML, use MVC. You want the overkill of webforms controls? MVC is far faster even for simple cases.
I did webforms for even applications ranging from simple to complex for 3 years, and I've been using MVC for almost 3 years now, and I can tell you MVC is far simpler for both cases. Webforms was designed to be familiar to people coming from a Windows Forms background, and that layer that created on top of the simple html/http request/response model of the web is overkill. The viewstate for example is designed to give the programmer the sense that state is continuous through the user's interaction, as if it were a webforms app, to hide the request/response web model from the programmer. But this is overkill and actually makes things more difficult to debug and work around. Having to tweak what goes into viewstate and what doesn't. For those who do it alot it is probably second nature, but it is an unnatural layer of abstraction over how the web works.
Try to do something as simple as a small survey that has a dynamic list of questions. On postback, even though you have no intention of showing the user the form again, in order to capture the user's response you must recreate the entire form, and make sure you do it in just the right event handler in the pipeline. In MVC, all you need is a POCO in the Action method parameter.