Within the body area, there are a couple of considerations. The first is, do you want a sidebar? Sidebars are very useful and can contain a nearly unlimited amount of different widgets, but they aren't for everyone. Some site owners prefer to have full-width pages. Do you want the sidebar on the left or right? Do you want the ability to have a sidebar on some pages and no sidebar on others?
All themes at Cheerful Themes (all Genesis Child Themes in general) provide you with the option of a left sidebar, a right sidebar, or no sidebar. This can be changed easily across your entire site or on an individual post/page basis. Some older child themes even provide you with the option of having 2 sidebars on either side. Cheerful themes do not have that option (I think it's just a bit too much), but I want you to be aware it does exist.
Within the body area, there are additional elements you may want. Do you want a hero image on your posts and pages? Perhaps the featured image? Do you need an affiliate link notification area? Do you need social sharing icons? Do you want to add a personal signature to your posts? Do you want a styled author box with your details on your posts?
These are little details, but most themes have things like these coded into them. There are also plugins to add functions that your theme doesn't have, but the less plugins you have, the faster everything runs.