The castle in LoS reminded me of the Castle from Van helsing movie, 3 towers, all snowy and blowing, giant chains, but I loved the gothic design of the castle in LoS, it was huge, and the Castle in every game basicly since it could had a formal yet gothic design to it, Dracula maybe a demon, but hes been labled the "prince of darkness" "king of demons" etc, so its safe to assume in the demon relm, Dracula Is hailed as a savour to them, (at least the original timeline dracula) for rebeling against god, this new one seems to rebeled against satan, but even so Vlad Tepes if my readings were right, adopted Christianity after his first exile. and was a holy knight Like gabe, but all in all I do love gothic design in buildings, it just brings a sense of class not seen anymore, though im also fond of victorian era things to (hence my home in rl)
as for simon's theme, the first time I ever heard it was Castlevania Bloodlines