Just to add my tuppence to the mix ( and I am welsh so not welsh bashing).
Wales unfortunately like many other areas of the UK has been hit very hard by the recession. Many of the large industries have up sticks and moved abroad leaving thousands out of work. With wages much lower than some parts of the UK, many people cannot afford to fly.
I believe that CWL will only prosper and expand when the economy recovers. The WAG can help this, not by throwing money at routes and spending on terminal development, but by doing all it can to attract high tech industry to the area with high paid jobs and to retain graduates and workers in the area so they don't have to move to London or bigger UK cities for work. The more disposable income a person has the more they spend and therefore are more likely to travel more.
I'm not an expert in this field and know that I will get shot down from the experts but just wanted to put forward my thoughts :-)