Castlevania: Rhondo of Blood has been pretty good to me so far, I think my only real issue with it at the moment is that the sub-weapons are not terribly great. They do pitiful damage compared to the whip, most bosses have means of blocking or dodging them, and while item crash is still great, this is a Classicvania title, so your score is affected detrimentally if you consume too many hearts.

Also, acquiring a key item to unlock the imprisoned cells is a neat idea until you realize that their cells and the key are in different sections of a stage and getting killed before you bring the key to the cell has the annoying consequence of you starting at a checkpoint past the key's location (the key is treated like a sub-weapon and sub-weapons are lost when killed) making it impossible to free the prisoner without going back to the title screen and restarting the stage all over.

It's also a bit weird that Marie, the first girl you rescue who becomes playable, is hands down better and more user friendly than Richter is. She's essentially easy mode to Richter's classic Castlevania mode. She basically has my two bread and butter moves for games like: Double Jump and a Slide, whereas Richter gets a situational backflip and nothing more, he doesn't even have the controllable whip from Castlevania IV.