Calculated Opt-In Rate

ACS does not provide its users with opt-in rate for any channel, nor with overlapped opt-in rate to see what % of users are opted-in to which channels. In order to get opt-in rate, you must run custom workflows and figure it out yourself. This is perhaps the #1 data point needed to understand your email / push / etc list, and I think ACS should calculate it for us out of the box.