I wish, although it seems fixing that requires convincing several million people that that terrorists are not actually hiding in every shadow. But somewhat related: fix baggage handling. There's no reason you should have to wait half an hour to get your bags after you get off the plane. Take care of that problem and people will be more willing to check their bags, which in turn will make boarding and exiting much smoother. Although airlines would have to get rid of their idiotic baggage fees, the improved efficiency should more than make up for it.
On the contrary--if you increase baggage fees, you could reduce the amount of baggage (making it easier to handle) and have more $-per-bag to spend on your fast baggage handling system.