Hi Derek,
I don't really uderstand what you mean by this: "On reading the forums to do your grading etc etc, you have no way of knowing that person X in actually OK - you need to refer to the gradebook?? So: I presume you have the gradebook open in another window and just check back to this??"
When I'm doing my grading, I'm just looking at the forum and clicking on "OK" (just like we can click on "Useful" in this forum). I can see that my "OK" is registered. I look at the gradebook from time to time to see the students who don't have an "OK" at the time they should have replied in a given forum, and so contact them to see what's up.
You can put all your forums in one category which will show a total grade for that category.
I've just started using the non-standard ForumNG (developed by Sam Marshall for the Open University) and find it far superior to the native Moodle ones. For example, you can see all the posts in one forum open on one page, either with all the posts expanded, or not. When you're replying to one message, you can see all the messages in the discussion and not just the previous one. Saves me a huge amount of time.
Cheers,
Glenys