First with your eco-system suggestion. This is a good idea as it would create a better simulation of the natural order of things. So from a story or flavour sense really, cool. However in gameplay sense, horrible. The reason that it would be horrible is that like any representation or simulation, as you approach closer to reality, the amount of computing power required skyrockets. Ex. I am a geographic analyst, who is someone who takes the real world and creates simulations which is used for predictions, planning, models, and observations. Just the few things you listed for your "ecosystem idea" requires the computer network of my university to sit and calculate for ten minutes, and that is just one instance in time, completely disregarding the passage of time and increasing influence of outside forces. DF already has a hard time tracking and recalculating the change in heat of lava passing through are lava pumps to get closer to the surface, and that it just one attribute. Now could you imagine DF trying to track tree cover, for grass survival, then the rate of grass decay, then the removal of grass, then the addition of things like the potash which helps growth, and the introduction of creatures changing their pathing based off of vegetation amounts. then to top it of add every other thing that DF already has to keep track of. omg god the LAG youd always be at 1 FPS. any who sorry for the rant it arrises from my fusration with the limitation of simulations....omg so many "tions". on the topic of the smithing, the elves of DnD can smith because they do not abhor the thought of burning wood, they dont overly and excessively do it, but they still do it. The elves of DF have no heat source with which to smith or smelt, and any metals that can be smithed by hand would be useless except as a heavy blunt weapon which would break after a few hits. On the topic of the trade Toady already anounced this as part of the Trade arc.