Headings - This is H3
Using different headings is important to display the hierarchy of information on the page. Additionally, search engines will look out for headings to understand how your content is organised. The use of heading tags (between H1 and H4) indicate the importance of your information to search engines.
Larger, bolder text signifies more importance than smaller, lighter text. H1 should always be the most noticeable text on the page then H2, then H3 and so on. These features show to the user the importance of the content and help increase scanability, legibility and readability.
Headings - This is H4
The page title is automatically marked as the H1 – there should only be one H1 per page (the CMS will not allow you to enter another). The subtitle is automatically marked as the H2 (again the CMS will not allow you to add further H2s).
This leaves you with H3 and H4 to use as appropriate to organise your page content.
Another in-page element you can use is thesyle. This has a rollover and non rollover state on desktops or a tap/non-tap state on mobile (try it).