Add custom size offsets for rendering and custom delimiter styles

[Divide-By-0]

This would look like a 'custom' option in each dropdown, which upon selection, spawns

1. for sizes, a +- dropdown, and a textbox where the user can specify the size diff as an integer
2. for delimiters, two custom textboxes for start and end

Feedback:

Your automatic makes formulas too small compared to text. See attached 02-Automatic.png.
How to get around the problem, I know. For example, I can increase text font size, select auto, render formulas, and then decrease the font size. But tools are made to make things easier.
Therefore, I propose to add the ability to set the custom font size of formulas - absolute (16 or 18...) or relative (auto -2, -1, 0, +1, +2)
Also I propose to add Delimiter Style $...$ or custom Delimiter Style.