imo, the best way to think of Agenda notes and content today is that each note is a sheet of paper. Searches and overviews let you view a subset of those sheets of paper.
If you think of how you might write tasks or notes on sheets of paper, that’s what you can do with Agenda. That means manually organizing things the way that you want them to appear. It also means making tradeoffs. If you want to see tasks separately from prose, then you need them in separate notes and ways to view them separately, perhaps with tags and overviews. If you want to mix tasks and prose in the same note, then you will see them together and just have to focus on the part of the note that you’re interested in and ignore the rest.
Yes lots of people want to filter to just see tasks, and yes it’s on the roadmap, but I’m telling you what’s possible with Agenda today.
Beyond that, the approach available today is to use scripts / workflows / etc to process and modify the text content of the notes. e.g. creating tasks in OmniFocus: Add todos to OmniFocus
So… I think of it as sheets of paper that are easy to use. It’s easier to cut and paste than it is to rewrite. It has some nice formatting. But, it’s smart sheets of paper, it doesn’t have the kind of atomicity as task managers. If you want to use some external automation to process the content, you can give it a shot. Though you can see some atomicity at work, e.g. in checklists where you can move checked items to the bottom. Drew and Alex have stated that there is more to come in that regard.
Reminders integration works well, when it works. I’ve repeatedly had bad experiences with it, so I’ve deemed Reminders untrustworthy and don’t use that feature anymore, which is a bummer. But I also don’t see many people reporting issues with it, so it’s possible there’s something wrong with my Reminders setup or I’m just unlucky there. I encourage you to use \remind and see if it works for you.