Similar to how the built in reminders app has a widget that is accessible from the lock screen, I would find it very useful to be able to view my agenda at a glance with a widget.
I haven't yet started on this. Your post has though reminded me of this as a missing feature which is likely to be expected by users in a task manager. I'll hopefully look to get work started on this sooner now rather than later.
I'd like to add to this suggestion, but not about the agenda.
My biggest problem with notifications is that they go away. Let's say I have a reminder at 5pm for a task. I use my phone and then I don't see it anymore. One application that doesn't do that is Apple's Reminders. The notification remain until you check it off.
My suggestion is to integrate with Reminders. The Taskmator application does this well.
Thanks for the suggestion! Highly likely this will be implemented in a future update.