This is the 2nd greatest thing to me about WikiTree, the Global Tree is numero uno to me. We can call them the way we see them, well to a point, or how we present our information in the Biography of our Profiles.
I do not write histories for my Profiles unless they did something really fantastic. Don't really care that Great Aunt Fannie had one ear bigger than the other. ;) I am here to produce chart of my ancestors if you will and just use a time line Bio.
My order is:
Name(s), Birth, Death, Burial, Residence(s). Marriage, Military Service. I just highlight them in Bold.
I don't use the Heading syntax of the == or ===, etc as i don't like the Table of Contents that much myself.
So my answer is if you want a ToC to appear, then use the equal signs to delineate the Headings. If you don't want a ToC, just make them Bold.
Now for the look, I find the == and === to be rather large and obtrusive anyways. The 5 ===== and 6 ====== are not as large and can be used nicely in a Bio without overwhelming the eye. And as Deb wrote, just use the __NOTOC__ if you don't want the Table of Contents to appear.
Go ahead and play. Put '''Born'' on your Bio and below that just keep adding ==Born==, ===Born=== out to 6 heading levels and hit preview. See what you like best and go for it.