Current actions does not support such tagging operations. Now I understand why you were looking for order looper. You need to loop through all orders and execute related actions by order type. Umm… yes that might be an interesting feature but first I have to check if such feature will be possible.
It seems you found the right solution by handling “Order Tagged” event. I suggest you to use Order States instead of Order tags. It will better suit your needs. You can handle Order State Changed event to check order properties and execute related actions. I used same approach on “Coupon Promotions” tutorial and it worked fine. Feel free to ask when needed.