Here's what you do:
-Get to stage 2 (regular)
-Get the KEY item from the candle when the big fucking monster is chasing you. YOU ONLY GET ONE CHANCE ON THE LEVEL
-Go down the area with the merman, and go to the right.
-Use the key item to open the door. Watch the cinema.
-Now you have MARIA AS A PLAYABLE CHARACTER!
So what's this mean? Well, Maria is like "easy mode" for the game. Why? Because she fucking moves quickly, you can CONTROL her jumps, she can DOUBLE JUMP, and she has long-ranged attacks. Did I mention that she also has far better magic items than Richter too?
Maria really shows you that old-school Castlevania difficulty is really built more around the slow-moving Belmont character than anything else. If the game really is exactly like the original (although I remember getting Maria later on, so...), then you should be able to use her to go through the entire game, and just use Richter on the last boss fight if you want to see his ending.
Although I've found the remake pretty damn easy so far, and that includes using Richter. It's nice seeing an old-school platform/action game again. I think the original PCE CD version is still harder, and I'm glad you can unlock it. Also it gets a lot of hate, but I think it would have been cool if they included the Super Famicom version too. It had different level layouts.
I just need to unlock Rondo now so I can see if Jeremy Parish really is full of steaming nuggets o' shit or not.