Nice, but needs some work
This is a pretty good game, but it has some serious shortcomings and loopholes (many of which have already been pointed out) that could really improve it:
1 - The lumber loophole - buy as many lumber milsl as you can, build hovels for money and build some more lumber mills, with 30 mills you get lumber faster than you can sell it, which means you can buy anything.
2 - Selling takes waaaaay too long. Maybe have buttons to sell it in lumps of 10, 100 and 1000. This, together with the previous point, make the game just a matter of sitting with your finger on the -lumber key for 3 hours, which gets a little boring.
3 - I don't understand the carrying stats - sending 300 henchmen with mules along with my army to the lowest difficulty destination and they are still bringing home only some 200 silver out of the 500 found...
4 - Why can you only build 1 mine? Expecially when you can gain lumber so quickly, it is very boring having to sell lumber for 30 minutes so as to buy enough stone to build the keep.
5 - Maybe a bulk buy button for soldiers too?
But again, this is a fun game, I had fun and kept playing it for a good few hours before I got bored of sellign lumber!