Margaret talks about focusing on characters
In short romances the focus is inevitably on the two central characters, the heroine and hero, the story of how they meet, the problems they encounter, their emotions, the resolution, and the inevitable happy ending. It needs to be a good medium between narrative and action. Too much narrative slows down the pace; readers soon get tired, and perhaps even cast the book to one side before they’ve finished it – which is the last thing any author wants. And too little doesn’t give enough information. It’s all a matter of finding a suitable balance.
Flashbacks are good – so long as they’re not too long and involved. No one wants to read what is not important to the story, so again a happy medium needs to be found. The bare facts perhaps, so that readers know the reason heroine or hero are behaving as they do even though they don't know all the details. It’s sometimes good to leave things to the imagination.
It’s also important that secondary characters are not allowed to take over. They should only be used when essential to the story – to move it forward or reveal information that can add a twist. If a secondary character does become important then perhaps it’s because they deserve their own story – which happened to me when I wrote Rachel’s Retribution, resulting in my book, Abby’s Bodyguard.