If you would like to customize paragraph styles throughout your wiki articles you can do so with CSS in "Code View" within your WYSIWYG editor. To access code view:
1. Select More Misc (depicted by 3 vertical dots) on the WYSIWYG editor.
2. Select Code View depicted by (</>) in the More Misc dropdown.
Here you will be able to style your paragraph tags, and heading tags using inline CSS. Specifically addressing your inquiry of changing size you would use the following example.
<h1 style="font-size:35px;">I'm an H1 sized at 35px!</h1>
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