I just modified the current Casper theme version 4.0.5 to improve performance and some usability modifications. Blogged about it here Ghost: Casper theme customizations (ipiyush.me).
Following are the modifications that I have done.
- Adding page anchor links
- Lazy loading comments
- Enable smooth scrolling
- Remove JQuery dependencies (pending)
- Replace FitVids with Reframe.js for better performance (pending)
Thought of sharing here in case someone wants similar customizations to be done on their blog.