With all respect, every Castlevania soundtrack until Lords of Shadow was, in its own terms, from brilliant to very good. Even the Pachislot had good soundtracks.
Order of Ecclesia is one of the best soundtracks of the franchise, in terms of chord progressions, arrangements and melodies. Also in feeling.
And that are especifically the things missing from LoS.
First of all, Castlevania needs to sound like Castlevania, not like a movie. Let God of War, Soul Calibur, Gears of War, Call of Duty, and everything sound like a movie because that's how they always have been. It just doesn't fit in CV, as well as a fantasy setting doesn't fit.
And second, and even more important, and I've said this in more than one occasion, the biggest problem is that it isn't even good as a movie soundtrack.
Believe me, I don't want to sound big headed, but I've studied music for a lot of years, and LoS is nothing like classical music, and with classical I mean classical, romantic, baroque and every iteration that is commonly referred to as classical music. Chord progressions, arrangements, melodies and overall structure is very different.
And it isn't even good as a movie soundtrack. It lacks in melody and in every aspect that, not only excelled in Castlevania so far, but in every good soundtrack in general. Take for example something very different as Gladiator, OldBoy, Star Wars, Atonement, Once Upon a Time in America... everything has some things in common.
With LoS all I hear is what Araujo always does, whether it's another game or a movie. It is predictable, it lacks emotional impact and it never closes its ideas; it's always messing around with the same chord progressions and arrangements and it resets in the middle or near the end to start again with the same we've been hearing.
Mirror of Fate tried for a while to correct some of these issues, but in the end it ended up falling in the same traps and repeating the same mistakes.
I could explain it in more technical terms but there's no point on that. I'm sure there's a lot of people that agrees with this point of view.
You can sound like a movie and still be a hell of a soundtrack. Just listen to what Hans Zimmer did for the Metal Gear franchise, or some of Steve Jablonsky's works in the VG industry.
It could sound like the cutscenes from Lament of Innocence when it tries to be emotional for a critical moment of the plot, it could sound like CV64 when it's trying to set a mood, and it could be like many Soul Calibur themes if it wants to sound like a battle theme and still be excellent music.
But it's none of that.
It's just... Araujo.