Yes, I agree. The long load times to visit other cities is frustrating. By the time I load a city, the item I was hoping to buy is gone. It is very frustrating. This started after the mountain updates were added.
I would like to see the cool-down timer adjusted.
If you haven't bought anything, there is no timer. You can refresh GTHQ as much as you want. But after you buy something from another town, THEN the 30 second timer is enabled. The timer is kept active for, say, the next 5 minutes. Then the game goes back to unlimited refreshes.
This way, mayors have a chance to find and purchase the item they desire. You still have to deal with The Llamas, but they don't smell too bad.