Granted, if you build new pages in Share, you'll probably want to reuse standard Share components, like the header, footer, menus, etc. In that case it makes sense to stick with using Share technologies.
But you might be interested in knowing that you can build and wire in a web page that interoperates with other pages in Alfresco Share using totally different technologies.
Let's look at what is needed to build a page that works in Alfresco Share but which is built using JSP, for example. We can't totally escape the Surf configuration. But we only need three files to define the Share page: page, template-instance and template-type. The files are relatively small.
That's it! Now let's define the content for the JSP page. The JSP file needs to go within the Share expanded WAR area. The location and file is defined by the template-type definition.
And finally, here is the rendered custom JSP page within Share:
The new page obeys Share authentication. For example, if you enter the URL to the page when you're not logged into Share, you will be first redirected to the standard Share login page.