I think assignments need more visibility. I’ve found it very easy to not realise that I’ve been assigned something, and to lose track of whether I have anything currently assigned. If you want things that have been assigned to be dealt with, then the person being assigned needs to know, and be reminded, that they have things on their plate.
The most obvious place for that is, of course, notifications. Anything other than a manual self-assign should be called out in a notification. So if anyone else assigns you something, or even if the self-assign regex catches something, you should get a notification, because I trip that thing accidentally at least as often as I actually want it to do its thing. (It’s a good idea, don’t get me wrong, I’m just not very good at remembering that the magic words are always magic).
I also find myself forgetting that I have things to do simply by virtue of the fact that the assignment list, and even its existence, is somewhat buried. We have magic header entries for “New”, “Unread”, etc; why not “Assigned”, also?