Maybe change gears a little.
I love MathCAD, but hate the formating/documentation for formal write ups.
As others have mentioned, being able to use font styles for a table of contents, split the screen, and just flat out format a document.
I understand MathCAD is a tool, so I suggest making MathCAD integrate with a word processor.
this would pre-empt items like Microsoft Mathematics from eating into MathCADs core users ... students who stick to a particular software when they graduate
This will be a logical "add-on" for Microsoft Mathematics to expand into.
There are a few "free" word processor/office suites that this could be implemented on (Open Office, LibreOffice, etc) or you could license the technology
Writing a paper and I have to meet the requirements set forth by the graduate committee. They specify font, style, format ... which is ALL based on word processor styles.