Ah nuttynut - our eternal debate continues...
In answer to your post, yes, I do believe that architect's are the only people properly qualified to design buildings - I think popular opinion would support this, I certainly haven't come accross any company or business, not to mention bank or solicitor who feel comfortable using anyone else to design their buildings...strangely that's what keeps architect's in business.
...where the problem lies, as you well know, is that the title of architect is not currently protected. This puts consumers at great risk and everyone knows of people who have been messed around by so called architects - while not saying that properly qualified architect's don't ever make mistakes, consumers can take solace in the stringent education requirements and membership requirements to the RIAI, they also have recourse to the RIAI should problems arise along the way.
While no legislation currently exists, provision has been made in the new Building Control Bill to protect the title of archtect for those properly qualified - details of who is deemed properly qualified may be found on line. Couldn't say when this legislation will come into force, but it will.
As before good luck to the OP, but in life there a few simple truths -you get what you pay for.