Especially: Sidebar vs. No Sidebar.
Also: Number of Columns.
I would like to have a sidebar on the homepage presenting stuff the site has to offer – but the category page should have nothing but posts from the category.
Both settings are possible via customizer – but only for both homepage and archive page – I would like to set them separately.
On a similar note: In my opinion GP has the potential to be a strong yet slick magazine theme. What it would need first, IMHO, is a (cleaner) integration of WP Show Posts and sections, plus as mentioned the possibility to give category-pages their own layout separate from the homepage.