Custom Conversions Shown on Email Dashboard

Just like you can set up a custom conversion for an A/B test and see it on the dashboard after the send, you should be able to do this with regular email sends. We want to know how each email did at converting our leads, and we can't get accurate data with the method we use now which is a smartlist looking for people who clicked the link in the email and filled out the form within a certain time frame.