@magma1447 - first, the dedication and responsiveness of the folks running this site are amazing. Thanks for thinking about this issue.
I think you are right that the number of challenges in the US has a whole is growing and will keep out-growing the server capacity. Can I suggest three possible feature-enhancements which could help (but which I realized would not be quick fixes):
1. Add a new "Exclude" option of "Unsure", which would mean than I could directly get, for examples, JUST the "Fulfilled" category rather the getting both the fulfilled plus unsure caches. I like to download and separately review the "fulfilled", the "not fulfilled", and the in between of "not sure" caches. So if I could exclude the unsures, the number of hits goes down by thousands. And then I would not have to do a fulfilled+unsure map, and add them to the virtual gps, and then subtract the unsures from the virtual gps. Eventually, the number of US challenge caches would probably exceed capacity again, but if you can exclude unsures, then you would probably delay the server issue for a few years.
2. Activate the multi-state selection capability on the map page, to allow me to click on more than one state at a time. If I am traveling to New England (with about 10 states) it is lots easier to get a US wide map and select only the geographic area I want, rather than doing 10 separate maps for each state and adding them all to my virtual gps. But with the server issues, I now have to do 51 state maps just to get the entirety of the US. If I can create multistate maps, I can knock out the US in two searches, both well under server capacity.
3. In the county drop down list, perhaps create a (somewhat arbitrary) country of "United States (Western States)" and "United States (Eastern States)" to essentially divide the US into two pieces. Ideally one could have the US, the US-W, and the US-E as options.
Anyway, thanks for thinking about this. John