Your preference between Castlevania II and III says a lot about your personality. One is a methodical, moody, starkly existential game about deciphering the obscure ramblings of a war-torn population, and the other is a Monster-mash action melee. One suits the pacing of a Jorowdowsky or Tarkovskiy movie, the other runs a marathon of James Whale Universal horror villians. One plays out of the story of a cursed man on an occult quest to resurrect a great evil, the other plays out the story of a holy man on a linear quest to exact justice. One is a brooding masterpiece and the other is a cheap rollercoaster.
First, I'll talk about Castlevania III. This is a game whose challenge is predicated on your avatar moving like a chunk of playdough with a very limited attack vector. Staircases are a commitment. All the content is linear except for three branching paths that take you through different sets of levels and allow you to encounter different secondary characters. One of these secondary characters moves like a real platformer character and is also a human spiderball, the other two sport resource-intensive gimmicks while nonetheless moving like molasses on heroin. Grant Dynasty is the underdog, the lower-class punk, and yet he shakes hands with the super-human, blows past the gilded cleric (Samus Aran in Eastern Europe) and the aristocratic half-demon Adrian Tepes, and runs with it. Honestly, it should have been Grant that married Sypha, displacing the entire history of the Belmont line from the 1300s on and making the franchise into something playable. Meanwhile the level design is wasteful and inconsistent, depending mostly on the spartan economy of restarts. You don't quite get booted back to the start, but you do get stripped of the Axe and hearts you depended on to defeat Death, which is worse because you have to consciously admit defeat instead of it being thrust upon you. Then there's losing on any of the three stages of the final battle and having to replay the same sections restart the fight from square one, the only games that reached a higher level of difficulty through restart abuse was Ninja Gaiden (the original series, all of them). With Grant and the handy emulator quick-saving, you can short-circuit this lazy game design and speed-run a game where, in ages past (the 80s), fathers can sons could only speculate about the last two levels.
It's got charm, sure, but maybe it's charm originates from unhealthy psychological elements to the hardcore game culture. The precise shine of the boss orbs, really tying the room of pixel art together, is just the sugar that makes the dark medicine go down.
Castlevania II on the other hand is a flawed but earnest attempt to go where Shadow of The Collosus and perhaps games like S.T.A.L.K.E.R. or Out Of This World succeeded in going - an ambience completely subsumed through the act of engaging the world. It's not perfect, but I think it's place in the history of the proverbial Metroidvania form has been under-recognized, it's a vestigial artifact left to the dustbin in grandma's attic. I'm dusting if off.
Both of the games are difficult but for different reasons, Simon's difficulty derives from a less cheap and more interesting kind of trick, requiring you to interpret obtuse bits of madness into equally obtuse actions, such as equipping the blue crystal you found randomly talking to people, kneeling next to a lake just like any other (it's the blue crystal, get it?) and waiting with no feedback for several seconds. Where the quicksave short-circuits the gameplay of Dracula's Curse, referencing a walkthrough short-circuits the gameplay of Simon's Quest. What's interesting though, is that there's something more substantial lurking under the flayed skin of this game. That something I deem special, a precursor to the atmospheric successes of Fumito Ueda and a lost prototype of what might have been for a genre all too saturated with culturally-sanctioned mediocrity. The commercial attempts to surpass Super Metroid and Castlevania: Symphony of the Night have all fallen short, fan-made attempts have stabbed in interesting directions regarding performance, but so far the mystery school has been neglected except for overzealous attempts that abuse the ratio of potential leads to real ones. Simon faces the same problem as he throws holy water on every brick, searching for destructible and/or fake walls.
In addition to tickling the sense that - because some blocks are not what they seem, anything is possible - Simon also shows you what it means to be alone. Trevor Belmont is like Nietzche's Superman rhymed with Conan - barbarian or O'brian, your pick. Simon is like Raskolnikov, like Telsa - he's a man in search not of justice but of answers, alienated, welcomed only by hooded scoundrels who peddle black magick, by loose women ravaged by syphilis, and crazed old witches waiting to die. The rest tell him he is unwelcome, either explicitly as you plod through the purple marshes and the while hallows toward the end, or implicitly through a sheer lack of common ground. This is perhaps the only Metroidvania to involve both open geography for its map and human populations, and it suitably chooses to make that social geography as sparse and internally molested as possible, with echoes of a post-Soviet landscape juxtaposed as post-Dracula. Hunger, fear, superstition, a horrible night to have a curse replete with the undead and their blasted lands. The geography plays with the 2D grid that the game is trapped in. Are staircases leading into the ground the entrances to caves, or adjustments to latitude? Dracula's Curse sees fit to answer that question (latitude) but Simon does not say. Everything is minimal. The protagonist is not even ostensibly referred to as Simon. It makes you wonder if his intentions investing these oak stakes and collecting these macabre artifacts, so profane yet so powerful, are entirely pure - reminds me of the Colossus hunting kid harboring guilt and mild necrophilic lust for the girlfriend he so vainly wishes to revive.
As flawed as Simon is - the game and the man - how can you not want to imbibe that kind of minimally provided atmosphere?
I'm not saying either of these games are great, in review, they are flawed like frozen amber. But one is flawed in a daring way and the other in a way that is tragically repeated in the decaying husk of AAA game development, albeit with better pacing and production values. It makes me deeply curious what a game like Simon's would be like with Planescape: Torment-level writing, unconstrained and unpretentious level design, and above all accessibility, because underneath the cloak is the rotting marrow of interactive literature.