Hi @jimmy
1. How to add an extra field
You can do this by passing in extra HTML to the $args array like so:
'html_before_fields' => '<input type="text" name="post_title" />'
2. Change the button text
Again, you can pass this in through the args:
'submit_value' => 'Make new thing!'
3. Pending
This is out of the scope of ACF, however, your above code will create a draft post which is kind of the same thing as pending. You would then need an Admin to edit and save the draft to publish it onto the site
Does that help?