It would be nice if the "Format Document" / "Format Selection" toolbar buttons in SSMS had a drop-down arrow next to them (like the "Other Windows" button in the Standard Toolbar). When pressing that arrow, all available Formatting Styles would appear in order for the user to select the formatting style to use. If the button was directly pressed, the default Style would be used.

If that is difficult, it would be nice to have a separate combobox containing all Styles and use that to perform the formatting when the button is pressed.