Back on topic, if I don't need help during the check-in process, I think this is a great idea.
If I DO need help during the check-in process, I think this is a great idea, because all the people that DON'T need help are no longer taking up space in the line in front of me.
People have used the self-checkout at supermarkets or convenience stores as an analogy. Sure, I've had bad experiences where certain stores are underemployed, everyone doing self-checkout has problems and no one can really help you. It stinks and I don't go back and if enough people are doing that, the store will probably rethink how many people they need staffing the joint at any one time. They're doing it wrong.
But at the majority of places where I shop, maybe 20-25% of the checkout lanes are self-checkout, and there's one dedicated employee (AT LEAST) overseeing those lanes to keep helping those who are having problems. And if those stores are very busy and even with the checkout lanes lines are forming, they keep opening up new checkout lanes until they're all open so people are waiting as little as possible. And I keep going back to those stores because they're doing it right. Or as right as possible.