In the very beginning of development of div2 we planned on including parts of FOV in the original game, but various constraints prevented us from doing so. However, FOV turned out much bigger than we ever expected, and has been in development since last summer. Looking at the amount of dialogue alone, it's about half div2.

Re: the engine, you're right, it was a complicated affair making it, but we should now be able to evolve it incrementally, and produce new content faster. In effort, if the gameplay content in FOV is 50% of div2, it cost us only about 10% of the div2 time to create the game's content, and the result imho is a lot better.