Cute is a Potent Spice

There are very few stories indeed that can't benefit from a dose of cute. However depending on what the genre of your story is, there is very much such a thing as too much cute.  If your are telling the romance of a golden retriever breeder the acceptable dose of cute will be extremely high.You can lay the cute on with a pain roller and no one will really care or even notice it in the context of your story.  If you are telling the story of a drug dealer who is framed for murder for an incontinent British butler the level of cute will be far, far lower, A single pig-tailed girl skipping down a sunny street will be jarring against that background. 
Unless you are Agatha Christie. In that case go for it.