Now you ask , simple - there exists a sample / test Solr application running that only responds with XML at this time. Can there be a good way to alter that output to HTML? Running Tomcat because the application server.

You must do XSLT changes. You will find a couple of samples built-in In my opinion... take a look at http://wiki.apache.org/solr/XsltResponseWriter

Take a look at VelocityResponseWriter (also known as Solritas) which utilizes Velocity templates to create output. It's substantially simpler to make use of than XSLT.

Here's an introduction.