the problem i have with curse of darkness is that it feels more like a seiken densetsu game than castlevania. i mean you could actually call this an rpg, something you can't even do with the handhelds(i haven't played ecclesia so i don't know if that feels more like one than usual either). the rest of the 3d games have more of a classic feel. lament goes kind of half and half, the metroid exploration is there, but you don't level up, which makes the game shorter, which to me, is a good thing actually.
i mean castlevania is initially an action series, and you don't want these games hitting the 20+ hour range. especially since you might need to go back and gain a few levels to take on the next boss or what have you. not much incentive to play a second time, relatively soon afterward, when it takes that much time to get through it once. that said i have enjoyed curse of darkness, and thankfully trevor does not level up.