Cloth is easy to produce, and a common export of many players that don't want to abuse prepared food or trap component price explosions. Since they no longer bring seeds for some unfathomable reason, their main utility is bringing rare animals, which can be quite a benefit.
Elves in worldgen are interesting in that they're the "zerg rush race".
Elves in fortress mode (petitioned for citizenship, that is) are interesting in that they're naturally friendly with wild animals, which makes them good animal trappers and tamers. Just make sure elves are alone when they might accidentally let that tiger loose, or they're the only one in the burrow to go set that cage trap right in front of a hungry tiger...
They used to be much more interesting, however, as they had a natural speed bonus that was much more significant and useful.
Since Threetoe's stories always showed elves having magic, though, I suspect that elves will eventually have some sort of druid magic available to them, if only some sort of tree-shaping spell, which makes them less of a lemming horde. I doubt there will be mass-produced magic wood swords capable of going up against steel, however, for reasons already mentioned repeatedly in this thread. Instead, I suspect it would be more like "Hear me, oh nice mr. apple tree! Hold that dwarf down while our tiger allies maul him!" (At which point, is triggered the dwarven AI for climbing up a tree, getting them stuck and unable to respond to tiger attacks...)