The sluggishness of the controls is an issue we are aware of, it is an issue with the image controls on the Mac platform. We will release an update in the next week or 2 to address that issue. We will need to use a different control type for adding pages and columns.
As for the redirects, The Insert and Update usually redirect to the details page, since you did not create a details page, they are both redirecting to the update page.
you can edit the insert and update behaviors to change where the redirects go.