Things to Consider When Choosing a WordPress Theme
How much do you need to customize your theme?
If you're happy with the out-of-the-box look and design of your theme then you probably don't need to concern yourself too much with customization.
On the other hand, if you do need to modify the design you'll need to make sure your site has the options that you need. Depending on the extent of the customizations needed, consider premium themes and page builders. And check each to make sure they have the options you need. See also, this page Theme Customization for information on theme customization.
Use a premium theme?
Premium theme are ones like Divi or Astra. They have costs of about $39 and up but have more features and versatility than free themes and should have all the tools needed to customize the site in whatever manner it needed. And importantly, a premium theme will have regular updates that keep it up to date with WordPress and major plugins like WooCommerce. It will also offer support and have forums where you can find answers and solutions to any issues you might encounter. Another advantage to premium themes is that most come with a additional templates that give you a variety of designs to choose from.
One last note, premium themes, because they have so many features can be slower loading than a light-weight theme with fewer features. So if you don't need the premium features there may not be any reason to use one.
Skill level versus theme features
Load speed
Responsive
Page Builders
Page builders are plugins that take the place of the default WordPress block editor. They allow for a greater design control than the default editor. And they contain a variety of useful elements. Like, quote sections, counters, accordions, flip cards, etc.. The also give you the ability to fine tune CSS elements either across the entire site or page by page.
Page builders do have a learning curve and require some familiarity with CSS elements. See this page for more information - Choosing Page Builder.