Forum

I do much the same thing. I use sum of ratings. I also use a 4-point scale and then multiply that by the number of posts I require. So if I want 3 posts for a forum, I set the max at 12 in settings. If they post 3 comments that meet the criteria (on time, substantive), they get 4 points for each post. If they are late or not substantive, they get less. If they don't post, they obviously don't get any rating. Then I let gradebook aggregate for me.