This map is not made for an eye candy, only for fun from a fan of this beautiful game.
For this first work description will be inside the map.
Next will soon come...and remember this is only a challenge to keep you entertained, enjoy!
As you've said the mission is challenging, however with the correct strategy it becomes very simple... till the spamming of the pig's troops! I managed to win just before the pig's armies touched my walls. To collect the stones I've built one more stone mine and sadly I couldn't build any more iron mines, as from the 5 ore places only 2 could be used. The key here to winning is the placing of your keep, if you place your keep near the stone mine, you will have 100+ stones in a few minutes, but then the gathering of iron becomes impossible, so the best strategy here is placing the keep near the iron mines. If you do so, you will automatically have the 31 iron ignots and 80 stones(only if you have 2 mines) when the pig's armies arrive. This scenario showed me that the designer has a "little" experience with scripting.
The balance is good. At the beginning the macemen made a little chaos in the area and destroyed some of the buildings, but after the economy was sat up, no events could harm it. The invasions were well scripted, but with a well fortificated castle and good placement of troops, they can easily be fended off. I give it a 4 as I won only for my 3rd try, but it is still far from outstanding.
The idea of the mission is good. But a little more could be added I think, you have a good imagination, but you shall expand your ideas more.
Map Design: 3
For your "first map" the terraining was pretty good. It showed you have made some maps before and you know how to use the tools, you simply rush your maps, that's why you can't make them look much more natural and much much better.
No story, just a little description, I can't give it a higher score, but if you manage to add a story I will probably change the score. :)