To the OP, thank you for creating a post with specific, detailed, tested, and helpful points. Finding information like this is a gem when browsing SimCity forums filled with threads agonizing over how terrible the game is. Granted, the game has nowhere near the scope and depth that I was hoping for, but amidst the bugs and glitches there are glimpses of genius. The UI and data layers are miles ahead of any other city simulator, and I can see how an agent-based system could result in interesting emergent behavior. In any case, all the other Sim City games I've played, including my cherished Sim City 2000, had a number of hacks you had to employ in order to craft the city you wanted. Anyone remember the tricks needed to make underwater tunnels or bridges that didn't need ramps? Part of playing any sim game is learning how to game the system, and I fully expect to do this in Sim City 5 as well.
In any case, I'd like to know more about these alternative shopping options for shopper sims. How do you determine which parks are "192-pop" parks? How many shoppers are satisfied by each park? How many shoppers does a library satisfy? I've seen spreadsheets that break down the worker/shopper/student and low/medium/high worker counts for different buildings, but hardly any of them agree on the shopping goods produced by commercial zones, much less the goods produced by buildings you lay down yourself. I like the idea of a park-filled residential/industrial city to supply goods to more densely packed residential/commercial cities, but I'm not sure how to balance the park-to-residence ratio.