I have to disagree with you on the chum numbers.
I accept your information on the relative abundance because I don't fish the Squamish regularly but I have been fishing it occasionally for more than forty years and apart from some abundant years about 10 years ago, what I saw on Monday looked about what I saw 30 and 40 years ago.
The dead springs(?) I observed were up near the Cheakamus but they were all about the size of large Chum. I didn't notice any large teeth or stripes but maybe I didn't look close enough, they were very fungus covered.
Chum retention... why?
A few years back when retention was allowed I retain a nickel bright coho, a very bright chum and a fairly clean Chum from the Squamish on the same day. We did taste comparison and the bright chum was the better fish. Admittedly the coloured Chum was not prime.
Don't bother spending $40 in gas to drive to Squamish to catch fish
$40 is about right to get to the Squamish but the Chilliwack costs me $60.
I like the Squamish because there is so much space. The other day nobody fished closer than about 40 yards. On the Chilliwack it is often 4 yards to the next fisher.