undo / history
It would be great to be able to have a HISTORY panel where you can jump back to a specific action or version like in Photoshop.

Hi there,
Most of the functions you have described already exists on the “Revision History” feature, released earlier this year. It enables you to preview older versions and changes made to your website and recover the version you like best.
Regarding your great suggestion to restore a specific action: let’s see the community’s feedback.