I don't think posting scores is technically necessary, I don't think it hurts either, so long as you're respectful if you happen to drub someone. I think the scrimmage period is for moving people around, trying offensive and defensive schemes, and in general sizing up your own team. I think a few straight up innings is fine, but I also like to have a few innings started with a baserunner on 1st or 2nd with no outs.