I agree with you - web forms is a great platform to learn. The capability to quickly develop a line-of-business web application cannot be understated. At Telerik, we continue to develop and support innovative new controls and features to make that type of application easier than ever to build.
If you're interested in combining ASP.NET technologies, I've written a white paper that describes how to best use these technologies together. It's called "Web Forms, MVC, Web API, SignalR. How can I choose just ONE?"
Finally, you should also know - we are adding new rendering options for all of our controls so that you can get a great mobile experience in your ASP.NET web applications with little extra effort. Check out our new Responsive Web Demo
to learn more about how the Telerik ASP.NET controls can help solve the mobile problem.