What, specifically can the passenger reasonably ask for? Is a refund on the ticket too much? Or a travel voucher? Would you say the amount would be comparable to the amount one is compensated for a bumped flight?

Also, who specifically should one ask for these things? The gate agents all disappeared until a couple of minutes before the boarding, and I couldn't get ahold of anyone on the customer service line (on hold for an hour before being disconnected). I wrote a letter to United the next day, and it went completely unanswered, so I concluded that they weren't interested in my repeat business.

This happened almost a year ago, and I haven't flown with them since.