Here's how the formal XML syntax would look (with our new URN namespaces ;))

<?xml version="1.0" encoding="UTF-8"?>
<f:view xmlns:f="jsf:core" xmlns:h="jsf:html" omitXmlDeclaration="true">
   <h:doctype lang="xhtml" type="strict"/>
   <h:html>
      <h:head>
      </h:head>
      <h:body>
        <h1>Hello World!</h1>
      </h:body>
   </h:html>
</f:view>

And we should be writing composite components like this:

<?xml version="1.0" encoding="UTF-8"?>
<ui:composition xmlns:ui="jsf:facelets" xmlns:cc="jsf:cc">
   <cc:interface>
      <cc:attribute name="name" required="true"/>
   </cc:interface>
   <cc:implementation>
      Hello, #{cc.attr.name}
   </cc:implementation>
</ui:composition>

The point being, no need for all the HTML wrapper garbage.

I'd even like to get rid of the ui:composition there and perhaps have something like "cc:component" or "cc:tag" as the wrapper.

We can also leverage the default namespace to cut out the unnecessary namespace prefixes:

<?xml version="1.0" encoding="UTF-8"?>
<component xmlns="jsf:cc">
   <interface>
      <attribute name="name" required="true"/>
   </interface>
   <implementation>
      Hello, #{cc.attr.name}
   </implementation>
</component>

Notice that I'm not really changing all that much in JSF to get to this point. It's really just a shift in thinking (and recommending).

-Dan