Overline style for annotation

I would like to have an overline text style that can be used for annotations. I've tried the klugey solutions like drawing lines in by hand, and putting underscores in a line of text above that which I want to overline. But I can see how an overline style might be useful to a broad range of users.

Related to this, how about incorporating Unicode into the annotation options?
There is an escape code that draw a line, \L. Here is an example:

Display
TextBox/C/N=text0/A=MC "This is \\[0some text\\[1\\S\\L0600\\M with an overline."


This uses the superscript escape to set the y location. You might also use the \y+ escape code.

See the details section of TextBox for more info.

As for unicode, that will require a major rewrite.