Distant Voice,
You're right. Taking a broader view might not be the same as taking a deep enough view.
The Coroner may indeed produce a better report than an enquiry, and can set a broad scope for the Inquest. However, they can also choose to focus on a very narrow question of the cause of death.
I'd still suggest that the Inquest process is rather different from other legal hearings though - the Coroner interrogates, and interested parties' questions are permitted by the Coroner. Questioning that seems to be "cross-examination" would only be permitted if it serves the Coroner's aims for the process; the Coroner may reasonably allow the next-of-kin, and their representatives, to be more general and probing in their questions. All written evidence and evidence given in person is still under oath; witnesses can decline to answer for fear of self-incrimination.
I just wanted to highlight some of the unusual features of the Inquest process that can account for it leading to rather different results than trials or other enquiries. As to which leads to the best picture of events: it depends on who conducts them and how.