I think that the prevalence of charming side characters points to something that Dracula adaptations often miss: This is ultimately a story about humanity being good.
The book is absolutely chock full of examples of people being good to each other: from the Romanian woman who gave Jonathan - a complete stranger - a rosary to keep him safe, to the suitors being good friends even after they realize they all proposed to the same woman, to the unnamed second mate taking watch when everyone is exhausted, to Mina talking to a lonely old man, to the people of Whitby preparing a funeral for the unnamed Captain of the Demeter and trying to befriend the dog.
When it comes down to it, this is about people banding together and helping each other. I find that adaptations often go very light on that aspect in favor of focusing on the charisma of the monster or the push and pull between Van Helsing and the Count. But the background of people caring about each other is very necessary to the story of the monster who feeds on them.
