Jordan Katz asks "what is a modern HTML authoring tool that answers my need?". The list of requirements seems pretty easy:

A tool that will not give me a headache and yet allow for some some sophistication (I'm not looking to write a book.) I want to easily and visually create table of contents, indices, etc. I want to drag links in and move links out. I want to chop out parts of tables and rearrange them. But above all, I don't want it to produce wrong HTML. No unwanted <br>'s, no extraneous <p>.

One problem that I see with most HTML editors is simple misuse of tags. For instance, practically every HTML editor out there has an indent button that inserts a <blockquote>, which by default achieves the desired effect, but isn't what the <blockquote> tag is supposed to be for. Similarly for <br> - you need to put vertical space between elements, the editor implements that as line breaks. Or they'll insert <font> tags when something like <tt> would have been a better choice. But I don't know. Considering how many people have built HTML editors and the results produced, you have to conclude that either nobody cares or the task of building an editor that produces good output is simply impossible.