I think any solution that does not use PHP will not replace WordPress for most users, unless WP itself stagnates. "Anyone" can install Word press on a cheap shared hosting device and get started. That's why I think a real WP alternative will need to be based on PHP (Laravel?)
I've migrated from WordPress to Laravel-based CMS before. There's Statamic, but it's not free, though. It's good, my users love it and I can easily add functionality in contrast to WordPress, you'd have to install a plugin or dig into the digustingly messy code. Hated it.
