A few years ago I would've said that a combo battle system was a dealbreaker for me. And in a way LoS completely took Castlevania away from me because of this. Then again, I am willing to accept change and I will definitely check out LoS2. But Castlevania just isn't the same anymore, and I blame combos for it. I have no problem with the new storyline, or anything else for that matter, but the combat is just so generic and dull. Every other modern action game does the same thing. I know the combat in the 2D games are incredibly basic, but that's my idea of fun, I guess. I'm too old.
The music was always important to me, which is kinda weird when I think about it. Why should music make or break a game? It doesn't make sense. But in Castlevania I was always absolutely OBSESSED with the music. That ended with LoS and MoF. Again, I'm willing to accept that things can't stay the same forever, but if there's one thing that was NEVER broken in Castlevania, it was the music. And yet they decided to "fix" it. The new music may not be a dealbreaker, but it's one of those little details that made me fall out of love with the series.