I love the fact that you can make notes in a campaign, and have them separated into DM and Public, however, what would make it even more useful would be being able to make note entries with their own titles and content, rather than just a single entry in both.

This would help with campaign tracking, allow for DMs to separate and organize their notes better, and make it much more useful.

Example:

Notes:

• Entry 1: Title 
  • Entry 1: DM Content
  • Entry 1: Player Content
• Entry 2: Title
  • Entry 2: DM Content
  • Entry 2: Player Content

OR

DM Notes

• Entry 1: Title
  • Content
• Entry 2: Title
  • Content

Player Notes

• Entry 1: Title
  • Content
• Entry 2: Title
  • Content

I agree.  A workaround/cludge at the moment is to use spoiler blocks to separate stuff out.

That’s a good idea for now, I’ll have to do that

Spoiler tags inside spoiler tags

I concur for the overall request.  Some additional food for thought ...

• It would be nice if the My Content section included a place where one could perhaps enter free-form notes that are unrelated to a campaign (and are not categorized as spells, backgrounds, monsters, etc.).  Perhaps include this in the Homebrew Creations as a Note type.  Perhaps create a special section for these notes (a Scriptorium?).  This gives the user (presumably a DM) a place to record house rules, house errata, or other information that is needed for reference.  Sure, we all keep these types of notes on our computer or in a notebook, but if we're shifting our focus online to D&D Beyond for other reference content, why not be able to add our own unstructured content?
• This might more related to Game Management (which I know is being developed), but it would be nice to have a place where we can keep a Campaign Journal with dated entries.  This can almost take a blog-like form where either the DM (or the party chronologer) can create entries, and the other members of the campaign can add comments.