Alrighty how about:
Proper civ sites: IE sites that actualy look how theyre supposed to be, like the one's toady was working a while back. Sprawling farmlands, towns that look like actual towns, protective wall included. Goblin towers that actualy look like towers, dwarf fortresses that are more then just a huge hole on the ground. Toady's plans for more immersive sites and how NPCs interact with it, and how the adventurer will be able to interact with them (housing, climbing walls, theft, breaking and entering, etc).
Worldgen scenarios: while worldgen is pretty awesome as it is, it'd be nice to see some worlds in which things went terribly wrong due to a scripted event and now a demon is amassing an army to take over the world (like Tremoda in my favorite threetoe story), or a naive wizard caused an undead plague to devastate most of the landscape, or even a world in which peace reings for a thousand years and all races are on good term with eachother. Conditions for said scenarios happening in normal worldgen, pre scripted scenarios and giving the players the power of choice over them.
NPC interaction: what will NPCs be willing to offer you, and how will they react to you as an adventurer, fortress or otherwise? How NPCs will interact with eachother, and how their individual personalities affect the player and everything else around them? Are NPCs really going to get their own personalities like our dear fortress dwarves? Will things such as NPC psychopaths, criminals, hired assassins, travelling heroes, reclusive wizards and madmen NPCs be possible?