Hi Ben,
The best starting point for changes like these is our Themer’s Guide, which covers how to safely override and customize our templates.
How can I change the βEvents for March 2015β² header on the calendar view from an h2 to an h1?
If you create an override for month/content.php by initially copying the theme’s default version of the template, you will find the following line of code:
<h2 class="tribe-events-page-title"><?php tribe_events_title() ?></h2>
Simply modify to use <h1> tags π
Also how can I change the event title within the day boxes on the calendar itself from an h3 to just body copy?
It’s a similar process, but the template you would be interested in is month/single-event.php.
I hope that helps!