Checking for new activity in Stack Overflow questions via API - best minimal approach?

I'm building a notification service that tracks updates to Stack Overflow questions (new answers/comments) and need the most efficient way to detect if any changes occurred since last check. I'm using the /questions/{id}/timeline endpoint with these parameters

site=stackoverflow
fromdate={last_check_timestamp}
pagesize=1

Is this the most lightweight method to detect any new activity (answers/comments/edits)?

Are there any caveats with the timeline endpoint I should be aware of?

Would checking /questions/{id}?filter=!BhNhTkF7J7vS1yZYE0 and comparing last_activity_date be more reliable?

What's the proper way to handle deleted posts/activities in this flow?