A little known fact about this film to many folks is that Little Nemo was made as an attempted collaboration between American and Japanese animation studios planned during the early 1980s. However, differences in the creative direction of the film led to enough disputes between both sides that it took years before the film finally got a theatrical release, which shows rather prominently in how the animation and plot to this are laid out. The look and feel for both are very Western-influenced as Little Nemo looks almost like a Disney film with its character designs and scenery, while sporting fluid movements and animated sequences. For an 80s anime, Little Nemo is easily among one of the better-looking animated films I've seen from the decade, being on par with Studio Ghibli films made during the time.
In terms of its plot and characters though, Little Nemo is rather underwhelming in both departments if you're not this baby's intended target audience of younger children. The cast mostly fill simple character types related to Western animated films and the plot's rather haphazard pace limit any world-building or character exploration that could have been utilized. The plot for it also milks a number of storytelling cliches that never get explored as Nemo is the "chosen one" to be Slumberland's prince, a typical good vs evil conflict involving the Nightmare King in the movie's later half, a number of the Slumberland residents looking like those part of the circus troupe he encountered at the start of the film and an attempt at incorporating some sort of moral related to Nemo's adventure. Pretty much, the film's intent is to keep its plot and characters as simple as possible for its target audience while anyone older may keep wondering why certain stuff to it is never explored.
Little Nemo also has its sloppy points in its writing. The later third of the movie features a couple points where Nemo is in some sort of hostile situation, yet he "wakes up" away from it only to discover he is still dreaming. The "wake up" bits function as a sort of deus ex machina to get Nemo out of trouble and seemed rather lazy in execution. The film's attempt at a moral is also rather questionable as it tries connecting a rather mundane incident that Nemo is involved with at the start of the film to later events in it when Nemo unintentionally triggers the threat of the Nightmare King for the film's second half. However, the events leading up to the moral being utilized are rather idiotic as a certain character was dumb enough to entrust the safety of his entire kingdom to Nemo (and not warning him of the danger in question) and our lead gets rather easily duped into triggering said events.
Overall, Little Nemo is mostly fare for younger children as its plot and characters are way too simple to appeal to older audiences in the same vain that many Studio Ghibli films are. I might have been in awe of the movie as a kid. But being older, it really loses its appeal when you begin to question the "whys" to it.
