All the questions you've provided can potentially help determine a media source's general intent, but if I have to choose one example that is broad enough to cover various types of media, it would be:
Is the purpose of the source to inform me about a topic?
This question can help assess whether the media source aims to provide information, which is often a fundamental intent behind many types of media, whether it's news, educational content, or informative articles. The other questions focus on specific outcomes (agreement, purchase, or support) that might not always apply to every media source.