create a child theme for a regular template - TwentyFifteen, for instance - the child looks exactly like the parent, until you start making modifications. Genesis child themes look vastly different from the parent, and from each other.
Themes Adding a Byline Changing H1 to H2 Removing the title One more line. 34 more bytes. Zero more lines. Zero more bytes. One less line. 30 less bytes. Four more lines. 150 more bytes. Five more lines. 214 more bytes. One more line. 65 more bytes.
Better for programmers who are used to functions and PHP. Marketability - Developers can brag that they know the Genesis framework. Variety - Hundreds of child theme to choose from. Continuity - Snippets which work on one child theme will likely work on any other theme. Reliability - The Genesis themes are built better than themes you’d find on other theme sites. Community - There are many resources that can help you - websites, videos and podcasts, and other developers.
Worse for people who are better at HTML markup vs. PHP. Learning curve - One more set of functions, hooks, etc. to learn. New technologies - Genesis took a while to be mobile ready. Also, there are no StudioPress themes with SASS partials. Design similarity - There’s a certain “sameness” to many of the Genesis themes.
use this plugin to make your code changes and modifications to your site. It's also perfectly okay to make the changes directly to the PHP. It is NOT okay to do both. It makes baby Jesus weep. (Or at least it makes other developers weep.)