How do you think Bloodstained compares with older Castlevania games?

I thought this game would be great. But to be honest it is not nearly as good as Dawn of Sorrow, SOTN, and PC Engine Dracula X IMO. The graphics are amazing, but everything else is unremarkable. Also, I am early in the game, but the difficulty spike on the Zangetsu boss was not good. Took me 50x to beat that boss. Anyway, just wondering if the game starts slow but gets better, is overrated, or if my opinion is just different than some of the glowing reviews.

By the way, the game seems a lot more difficult than the Castlevania games I listed above, is this true or not?