Thank you for your patience and understanding. I have just finished what I hope are the final changes to the quest system.
(I lost two hours because of a bug, only to find out that I had to start a new game to get the changes to work. This is one of the reasons why I do not want to release another 0.x version before I have finished the base systems with the 1.0 version.)
Now I need to create some quests to test it and the new combat system. Then, theoretically, it should just be a matter of writing the story. Although there will inevitably be some tweaking and refining to do. More advanced features will be left for the 1.1 release and beyond.