It really is a nice terminal considering all of the airports I've been to. Detroit Metro is pretty spacious and one of the things that I like is that it is pretty nicely lit. Some other cities' airports are usually big concrete slabs with narrow aisles. Inside the airport it truly is world class; outside there could be some upgrades with shuttle service, access to rapid transit [[another topic altogether!), better parking, green space and a true attachment to the area. There seems to be a detachment from the city and area it serves.