Newt's character is emblematic of a revolution in representation. Be sure to watch this video in it's entirety.
It was an incredibly good move to call out all those reviewers who were turned off by Newt. Their conclusions are manifestations of a stale, old misogynistic perspective on filmmaking. Newt is not only unique in his vulnerability and unapologetic quirkiness, he otherwise fits every other stereotype of a "default" character (white male, lead in a blockbuster, etc), making his personality all the more assertive and important in a landscape where lead characters and soulful personalities were treated as if they were mutually exclusive, thus also perpetuating stereotypical characters for underrepresented groups.
The comments made here about Harry are spot on, because he represents the last movement in the (awkward) symphony of post-modern heroes. Newt is an door opening on the New Sincerity Movement, bridging the painful gap between old archetypes and underrepresented personalities, making way for all in the future.
I also am holding a glimmer of evidence that this new franchise may be metafictive: The character's are given an uncharacteristic pause in the editing when the title (Fantastic Beasts and Where to Find Them) is mentioned. It's not much to go on, but there's years ahead of us wait for and listen through :)