I agree that flying in the Vancouver area has become busier and more complex that it was even just 10 years ago. I understand why it takes a new pilot longer to solo, or complete the PPL than it would at a small airfield, especially one without a tower.
The huge advantage to flying out of Boundary Bay (CZBB), Abbotsford (CYXX) or Victoria (CYYJ) is that from day one, students learn communication etiquette, dealing with ATC, and airmanship within a busy environment. Yes, some focus will be taken away from actual handling of the aircraft at first, but these are essential skills - especially in the real world!!! I would recommend any of these airports for training, and as others have already suggested, each has a few excellent schools to choose from. Flying in the Vancouver area is a busy place with many procedures and routes, yet within 30 minutes, there are plenty of uncontrolled airfields available also.
Just my $50 worth!
Happy Landings