enable frames around functions, defines, classes etc; now it's just blank background and it's difficult to read the function body or see between define and its description
enable "Source Code for this File" view, where you can see the source code from which the docs were generated "without" comments parsed by Doxygen
enable Tree View for easier browsing
enable full text search
make the Doxygen generated sources look a bit like the website for consistency; i know that customization is limited in Doxygen, but something could be done
add class diagrams \[suggested by EP in a mail thread\]
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