I still don´t fully understand why you could not use Message boards on your particular news documents? What is shown on the page (news title, news short description, news full description, news image and news attachment file) depends on transformation and (if needed) additional web part, like Attachment image gallery for example, however Message board web part can be added beneath, so it is independent on news page appearance. Second option, if existing Message boards does not fit your needs, is to develop a custom web part according to this article
If your scenario is special in some way I don´t understand, please make me some screenshots and send them to firstname.lastname@example.org (you can attach some further description as well). Thank you.