As for their composition, it seems odd that boulders can provide an unlimited amount of stone. Perhaps a limit on stone p/ boulder, or a new material that could be made from boulders (Stone blocks, as mentioned above)? This is all just the ravings of a lunatic and a relative newbie. I'd just like to see stoneworking playing a more valuable role in construction and the like.
And of course, a castle wall system would be pretty cool. But you'd have to make it ridiculously hard to build to stop uber-forts popping up all over the wilderness (perhaps quarries as rare as iron mines are now?)
Feel free to shoot me down on this. Just had some spare time and nothing better to do
