I was starting to get some ideas about interesting elves.
With dwarves, it's your dwarves that level up, that you want to protect. It makes perfect sense that dwarves are happy trading off stone-- stone is useless unless you do something with it.
We've all been assuming that elves would work pretty similarly to dwarves. But what if your elves were more like trained animals? What if it was your immobile trees that skilled up? A single tree might generate tasks, like a workshop does, and level itself up. Your elves would serve as a defense and hauling force, delivering meals and materials to trees, and defending them against evildoers (such as wood cutters). In other words-- all of your laborers had all tasks enabled, but couldn't skill up, while all of your workshops could skill up instead, and could be used for any sort of task. Wouldn't the elven mentality make a lot more sense after playing a few years of that game?
Let's look at how this would play out in a couple of fields:
Food gathering: I can't imagine elven farmers. One tree might drop fruit that could be scattered, much like planting a plot (probably larger, and less effective per square). A tree sent to "Fruiting" would eventually develop better and better fruit, leading to higher yield. Idle elves would gather plants from the fertilized squares.
Weaponry and clothing: One tree might periodically shed wood ideal for bowmaking. An idle elf might come and pick up the wood and fashion it into a bow. As more bows were made, the tree could become a legendary bowtree (while still only a dabbling fruit-tree). Since all elves were also military, elves would occasionally pick up a bow the same way dwarves go shopping.
Living spaces: Immobile beds would actually grow out of a tree assigned to "bedmaking" or whatever. One tree could eventually become a legendary barracks. (I don't see elves as being too particular about ownership.)
Trees would of course need food and water to prosper, the same way injured dwarves need it to survive. Trees would get moods, and melancholy. Trees would welcome new saplings to their fold-- if there were resources enough for all.
I think that this alternate way of looking at elven civilizations would resolve a lot of problems. Who needs balance when elven civilizations play under completely different rules? Who needs steel or adamantium?