RTE on a page should only ever sit 5 or 3 columns wide. And always inside a 1:3 layout.
There are very specific scenarios where you might need to make the RTE 9 columns wide (e.g. if you need to add a graphic in) but these exceptions are few and far between (e.g. full width Iframe graphics).
Please use the formatting available in the Formats dropdown (especially important in News and Stories).
H1 should never be used anywhere except the page banner.
H2X - use this sparingly, more likely to be used in promo and stat blocks for a big bold statement.
Body large can be used whenever standard paragraph text isn't big enough (e.g. some promo blocks use Body Large)
To add a styled link, highlight the text and FIRST select the formatting from the Formats dropdown. NEXT add your link using the link selector.