Very good question, hugeblack.
I'm going to change the sign-in process to allow users to show their photo ID only when they want to withdraw. That seems to be the process that a few other US-based companies are following.
This would be a very bad decision, the service allows deposits but the depositor must complete KYC to withdraw, and note that since you are a service registered in the United States, you will be subject to the OFAC list and many countries will be banned from using your service.
I appreciate this information, hugeblack. Can you post some exchanges that have registered MSB activities other than "Money transmitter"? I'd be interested to see how they registered.
You need to consult a specialist but I think that the US license is the last license you want as an instant exchange because it will be mandatory for you to impose KYC, you will be forced to reject documents from many countries, and you will not be able to compete other services like coinbase.