I'm a differential geometer and work on low-dimensional gauge theory and topology, at least when I'm not teaching. I write a small amount of poetry, rather slowly, but publish little. This plot should be discovered rather than announced, so show, don't tell. Finally, don't forget to throw in distractions and sub-plots. From the player's perspective, finishing a good text adventure game can be a little sad in the same way that finishing a novel means leaving behind your favorite characters.
Atmosphere is enormously important and requires fine crafting.
Once a genre has been adopted, stick fairly closely to it. Extremities, I'm afraid. There is no substitute for extensive play-testing. About one-third of the code in a good game will be devoted to blind alleys and responses to wrong guesses by players. Writing a really general parser is a major but different undertaking, by far the hardest points being sensitivity to context and resolution of ambiguity.