This looks slick. I want to start marketing my themes/plugins as a website solution rather than bits and pieces for somewhat technical users. An onboarding experience like this presented to people totally new to WordPress could really help with conversion.

I wonder how it compares to One Click Demo Import plugin which does a similar thing by importing .xml, .wie, etc. https://wordpress.org/plugins/one-click-demo-import/

My only concern with WP Merlin would be including it directly in a theme and how slow theme authors might be to update it if ever there were a security issue. I'd prefer to have a theme show a notice on activation with link to install and run the plugin via WordPress.org.