You mean you can edit fields without touching code? If so, we have 2 extensions for this purpose: MB Builder extension or MB Template extension.
Regarding the text and image: yes, you can do that. You need to register a group which has 2 sub-fields: text and file_input (do not use any image fields here as they won't work for group):
$meta_boxes[] = array(
'title' => 'Meta Box Title',
'post_types' => 'custom-post-type',
'fields' => array(
array(
'id' => 'group',
'type' => 'group',
'clone' => true,
'fields' => array(
array(
'id' => 'text',
'name' => 'Text',
'type' => 'text',
),
array(
'id' => 'image',
'name' => 'Image',
'type' => 'file_input',
),
),
),
),
);
