Your hero must be likeable and sympathetic at all times. Like James Bond in the Roger Moore era, he’s quick with a quip, and is unruffled by any situation…
Also include either a kickass woman who can do the unacceptable things that would make your hero unlikeable, or a wise old soothsaying woman who speaks in parables and knows things that can’t be found on the internet. See also: sidekick comedy robot…
Despite possession of gigantic highly-advanced starships, wars are usually won by your hero and a few good marines. Death is optional. At the end, everything is as it was before, except your hero is richer, more powerful, and married to the right woman, who is never the kickass woman.
— Tips from Paul McAuley. Entire, lengthy, funny post can be read here.
(pic is, what else, a Vallejo.)