Reality is, you can't get away from the traditional Castlevania sound as easily as you might like and expect people to judge these scores on their own merits (particularly when it's done in a style that catches a lot of flack from VGM fans and matches a lot of the negative connotations thrown at western VGM).
I agree with both points... although I still agree and bound by what I said to Adam's quote above. Castlevania is defined by it's music as much as it's gameplay like many other franchises and yeah... I feel western VGM does take the same route way too often. That opinion of mine may be erroneous but it doesn't mean I'm complete inapproachable with that style.
Again, though, everything I've read about this development team indicates they are simply in it to milk the franchise to make a name for themselves and then get out, despite their subpar history....
I know I'm going to creep into game territory (discussion) with this one, but I wouldn't worry about this to the level you are. Mercury Steam may have put themselves on "the map" with the first LoS... but if the reaction to the two following games is an indication (really after LoS2 released NO ONE I knew was talking about it and I don't think it's selling well despite getting decent reviews) I don't think MS is going to have any long lasting legacy for working on the franchise. I personally feel if Mercury Steam was going to work on games beyond this one Konami would put an end to it anyway as they seem to be losing people.
As for Oscar Araujo's music, while I'm not completely on board with it, does strike me as something that will probably live beyond the games it comes from with VGM fans. I know that last part really narrows down the scope of such a compliment but so many (too many) people treat VGM as a disposable backdrop in games... but those are people that hop from game to game and rarely reflect back on what they've played years later.
Same deal with the N64 Castlevania's soundtrack, it got too far away from what people expect/enjoy about the series' music and it was hammered accordingly. And Castlevania Judgement (a fighting game) proved that you can't just throw some crappily arranged classic Castlevania melodies into a game and expect it to work.
Personally I think that's just a bad comparison. Castlevania 64 is such a different (and somewhat convoluted) beast than many of other games in the series that I wouldn't expect it to adhere to all the franchise's calling cards. I know some people liked that game but I think most considered it a failure and Konami pretty much closed the book on it accordingly.
Additionally, while I agree you can't just throw a few classic CV tracks into a vastly different soundtrack, I ironically feel this way about CV4. The reprises of Bloody Tears, Beginning and Vampire Killer are among that score's weakest moments IMO.