Ben,
Regarding bboard, if showing attachments inline is not a setting in the package manager, it should be straight-forward to add it as an option. I understand you're starting on OpenACS (welcome!) so you could just nag someone to do it for you 😊
Regarding news, it does allow comments. I can't remember if it's a setting on the package manager, but it does allow comments. See this news item for example: http://dev.openacs.org/news/item?item_id=46161
