Mezzanine has a built-in search engine and API, integration with services like Disqus, Gravatar, Google Analytics, Twitter, bit.ly, Akismet, a blog and a good selection of templates available out of the box.
Editing of blog posts or themes and widgets can be done on the frontend as long as the user is logged in with an Admin account. This make Mezzanine very easy to use and manage even for people who may not be experienced at all in programming.
Django CMS project is a large and complex project, comparable to Wordpress. As such, it may be too much for a simple personal blog considering that it has many features that may never be used in that particular occasion.
Installing Wagtail on a remote server is a little more complicated than FTPing a bunch of files. Furthermore there's no ecosystem for plugins and themes so it can only be fully extended by a developer experienced with Django.