Your content manager will love you, especially with the user friendly page editing tool.
You need a custom placeholder, CMS plugin make your developer happy.
You want to inject a custom Django application to the page tree, just hook it.
The flexibility offered by Django framework permit to easily add new custom feature to your CMS.
The community provide a good choice of Django-CMS applications, like blog, news, poll, etc., and you always find good support from the enthusiasts community of developer. Review collected by and hosted on G2.com.