That said, if I was forced to choose a "user friendly" CMS, I'd go with Drupal 8 (when it's released). The reasoning? It still has the client-facing tooling that non techy users expect, but is built on top of the Symfony core, following all relevant standards.
It's a little while away though, unfortunately. Depending on the site, my answer nowadays is a Silex API for the data they want to work on, and a React + Flux front-end. That's too much work for a $2k site however; WordPress is so entrenched that any replacement needs to be able to answer the plugins question successfully to overtake it.
And that plugin can help you with the migration: https://github.com/SchumacherFM/wordpress-to-hugo-exporter
Hugo is more for nerds than the average WordPress blogger.
edit to add https://github.com/TryGhost/Ghost
I'd love to see a user-friendly GUI backed by Jekyll.
We in technology are not "most people".