I keep saying this - and I speak from experience as someone who does this sort of research and commissions it - if Cardiff had such a clearly proven market, it would have more operators exploiting them. Airlines are there to make money. They will exploit opportunities to make money. They won't just connect places for fun - they need proof that a commercial opportunity exists. If they can't see that market, and can't prove it's there - they won't go there.
The fact that Cardiff is NOT getting loads of new routes says one thing loudly and clearly - A SUFFICIENT MARKET IS NOT THERE.
I am quite sure the new owners of Regional know this, and will be focusing their efforts on routes that give them more chances of success.
TA