We've really just scratched the surface of Dojo widgets that could be useful in developing geospatial apps. I encourage you to browse through the Dijit documentation [1] to see some of the other UI elements that are available. Here are a few that are particularly useful:
You should also keep in mind that Dojo is just one of many JS frameworks that can be used to develop your apps. The Guide section of the SDK includes a page on how other frameworks [2] can be integrated into an Esri JS API app.