Being able to exclude constituents from the Workflow would be very helpful. For example, we have a Workflow set up so first-time donors immediately get sent a Welcome Email. Two weeks later they will get the second Welcome Email and two weeks after that they'll get the final Welcome Email. But, there might be an instance where we have a first time donor but we don't want them to receive the Welcome Series and we don't want to mark them as DNC since we want to send them other emails.