When you first created your Heroic account, we gave you a font palette as part of the package.
Every font palette comes with a total of 9 font styles -- 6 headline styles and 3 body text styles.
In our experience, 6 headline sizes and 3 body font sizes give you all of the flexibility you need to build a professional website that positions you well.
6 Headline and 3 body text sizes means you have 9 text styles to choose from.
In case you think that's not a lot, just take a look at Amazon. It's got a billion pages, but only 6 headline and 3 body text styles.
So it's not about having a hundred sizes of text -- it's about using a great selection of them, consistently.
Seeing & adjusting your font palette
You can see & adjust your current font palette at Global Styles > Header Styles and Global Styles > Paragraph Styles
Each headline and body text style has its own settings. To adjust one, just click on it to reveal its individual properties.
Keep in mind that adjusting a font style here will update that style everywhere it's used on your site -- across all pages.
This means you shouldn't use the Global Fonts for a special or one-off font treatment on a single page. You should, instead, create a custom style right inside the editor on your page using the Custom style adjustment.