Economic activity is based upon a simple precept. Return on investment.
The cost of upgrades for basic resource buildings goes up waaaay too fast.
To upgrade my mine to level 4 requires:
13,000 gold (a bit high...but not really a problem)
720 wood (over a day's production...but ok)
300 stone (again high...but doable...i actually have to search to find ways to spend stone)
18 iron (thats 9 hours production...acceptable)
15 steel ingots?!?
(ok...this is where it starts to get a bit crazy...15 ingots requires that you first make 15 coal at 15 minutes each, then add those 15 coal with 30 iron to produce the steel bars...at 30 minutes each...so thats over 15 hours...still under a day)
5 medium tool kits
ARE YOU CRAZY?!? Or is this game just for pay for play?
Each medium tool kit requires
3 tool kits
2 forged steel bars
Some gold and iron and wood and stone...meh they are no problem.
So, each forged bar requires ANOTHER 3 steel bars and 4 ore AND takes an hour to build...
Each toolkit requires 4 hours and gold and stone and wood...
IT'S the time!
To do this upgrade (which adds a total of 12 iron/day) requires that I tie up the production of my mine, my forge AND my smithy for days! (See the following table)
Step Ore req Time Req
Ore 18 9 hrs mine production
Steel bars 30 15 hrs mine production + 225 minutes forging coal + 7.5 hours forging bars
15 tool kits 60 30 hrs mine production + 15 hours smithing the toolkits
10 forged bars 80 40 hrs mine production + 10 hours forging tempered bars
5 medium kits 40 20 hrs mine production + 30 hours smithing medium kits
Ok, assuming you can always come up with the Gold, Wood, and Stone (which sort of negates them as "BASIC" resources doesn't it?) you need to use the entire production of you mine for more than FIVE days, the entire output of your forge for 2.5 days, and the entire output of your smithy for 2 days.
Those numbers are with no delays (basically you are waiting with all necessary requirements for the second you can start the next step), and the only time that can be reduced is for the mine, as you might loot the iron instead.
Conclusion? Medium kits shouldn't be required until you are upgrading to Ore Pit (level 5) when you will have (or at least CAN have) two iron mines, two foundries, and two smithies. Same argument (only more so!) applies to level 4 timber hut. Either that, or this is the most effective way to spend crystals.
Edited for the correct ratio of resources on tempered steel bars (3 steel bars + 4 ore).
The bureaucracy is expanding to meet the needs of the expanding bureaucracy.