style

On the surface, HG looks like a pulp space adventure. However, that doesn’t define it. In fact, it shouldn’t be describable by any sole genre: it aims to blend comedy, drama, adventure, surrealism, horror, mystery, etc. It is thus quite hard to tell what fits the style and what doesn’t.

realism

In terms of laws of nature, some realism should be kept; unnatural things or behaviour should be explainable (unless there is specific reason to do otherwise); but other than that characters and societies have full freedom to be weird.

adventure

Used as a main source of plot advancement.

humor

• subtle is better than bold, though latter has its place too
• parodies are fine as long as they are not dominant
• forth wall shouldn’t be actually broken, though occasional subtle hints on it are fine

drama

Drama is always welcome, both as means for additional humor effect and actual serious drama.

moral choices and ambiguity

Moral choices should be common, sometimes without any ‘good’ option (or, perhaps, with one leading to dead end).