I read your post and can't disagree more. You boast that the Global Trade HQ has more trades than the New York Stock Exchange. However, with the NYSE I can at least see and buy everything that is for sale. I should be able to search for the item I am looking for and if in high demand, I better be quick to get it. If I'm not quick enough, I should be able to see any secondary items I am looking for. Why do I only have a choice of 20 or so items? Why are there always duplicate items? I constantly see a ton of light bulbs, or watches. I just want to see everything available. I know there is a ton more items that are being advertised elsewhere.
Also, with the 30 second refresh, when I go to another city to buy the item, I go back to the Headquarters and the items is still there? Why? It should go away as soon as it is purchased eliminating confusion of another mayor shopping for the same item but is unavailable to them. I have noticed this as the 30 second refresh gets down to single digits, any other city I go to, to buy an item being advertised is already gone.
I see expansion materials frequently when shopping with my 10k population level 8 city. But rarely with my 500k population level 45 city. Why? I get that there is more available to the level 45 city. This being the reason for the necessity of a search menu. I know the expansion materials are out there. Why can't I find them with my level 45 city, but they are there all day and night with my level 8 city?