What’s the best “insert all images” plugin?

Skip the Plugin. You don’t need a PLugin merely to insert all images attached to a post.

Just use the shortcode (also available as an “Insert Gallery” button in the Media Manager on the Edit Post screen).

EDIT

IF you want to display commentary for each one, here’s a suggestion:

1. Use the “caption” field in the Media Manager, to add your commentary for each image
2. Pass the size="large" and columns="1" parameters to the shortcode, e.g. [gallery size="large" columns="1", to output a single column of large-sized images, each of which will output your commentary as their caption.