Hi Ben,
The simple route: I think that going pro would give you more options, therefore I think the portfolio section could be included (the theme author is the best person to shed some light on this).
The more complex route: if you’re familiar with code, then you’ll need to find the sections directory and add a new section to the ones already there, let’s say, portfolio.php. Then it’s up to you to add the appropriate markup and php code to this file according to the way you’d like the portfolio to be displayed.
Each section is called via the WP Customizer and displayed on the front-page.php file (as far as I can see from browsing the code available here, on the WP.org repository). This means that you’ll need to work with the Customizer as well. Finally, you’ll want to style the new section, which is more CSS work.
In a nutshell, it’s quite a bit of work and to carry it out yourself, your WP theme development skills need to be between intermediate and advanced.
Which route you choose to go, pretty much depends on your time and skill.
I hope this helps clarify what’s involved in your requirement.
Cheers!
-Maria Antonietta