As for Qatar it has to be at least 5 weekly to attract the business passengers and i highly doubt they'll go to all the effort just to scrap it after 8 months! Personally I think the route will do fine and I laugh when people complain about CWL not having routes but then when they get them complain it won't work!
There has been plenty of advertising of the route on all media Wales Online seem to do an article including it every week! And I've seen advertising at Temple meads and Cardiff Central. Also Qatar is advertising Cardiff on the front of their web page right now.
I fly will KLM a lot and always find them cheaper and easier than Heathrow and I'm not the only one.
Enjoy Inverness i hear it's a lovely place and hopefully one day Flybe might operate the route from CWL.