rst-toc-insert-style

rst-toc-insert-style is a variable defined in `rst.el'.
Its value is

fixed

Documentation:
Insertion style for table-of-contents.
Set this to one of the following values to determine numbering and
indentation style:
- `plain': no numbering (fixed indentation)
- `fixed': numbering, but fixed indentation
- `aligned': numbering, titles aligned under each other
- `listed': numbering, with dashes like list items (EXPERIMENTAL)

You can customize this variable.