There was never a movie like this, and never again. Bold enough to blend fantasy, horror and sci-fi in a children story. Like a good classic children story is meant to be. With monsters and fun. (Oh, I remember, Neil Gaiman does it so well, too! Oh, and he was the one that said that "fairy tales are more than true: not because they tell us that dragons exist, but because they tell us that dragons can be beaten.")
A middle ground between Dante's goofier work and his forays into darkness, on rewatch I wish he had embraced the latter more. I never found Billy's hero's journey that compelling. The best segment of the film being Billy's mom's encounter with Gremlins, the bit where she first picks up the knife is truly suspenseful moment and Dante morphing the fireplace's glow into something nightmarish is masterful.
You can read many of Dante's films as satirical responses to Spielberg. Here, Gremlins subverts the relentless adorability of E.T. Starting from a similar premise--cute alien companion--Spielberg is content to let ET just be our buddy while Gizmo spawns murderous grotesques. The film then takes great delight in torturing our pal Gizmo for the duration. ET is a celebration of cuteness, Gremlins a violence against it.
Was never a particular fan of this one even as a kid. Much prefer Dante's 'The Howling'; that was a film that understood its genre and gave it a real subtext. Performances all around are weak, to be kind, especially the two young leads. Some inspired moments of lunacy and in-jokes but still results in a film that seems much longer than its run time. Effects hold up pretty good save some crowd and walking shots.