Cradle

Cradle is a starter theme that offers the classic WordPress experience with better defaults and extra features.

It kind of stands between _s and sage: It is somewhat opinionated (e.g. template files are organized in a separate directory, source files are automatically included), but remains within the WordPress ecosystem (e.g. does not use Laravel Blade templates).

The theme used to include a lot of modifications to how WordPress behaves, which are now moved to mu-plugins. Currently it is more bare-bones, but still supports some common components and features.

I have used Cradle on dozens of client websites, including e-commerce projects, and found it easier to build and require less maintenance compared to an off-the-shelf template.