How the hell did nobody recommend Bloodlines. Like Bloodlines is brutal as fuck (don’t feel bad about looking up some passwords if you run out of lives and continues) but is the best game in the series outside of Rondo.
Castlevania 3 is good, but I feel like 1 is a lot tighter and prefer it.
I think all the exploratory ones are pretty good, although I haven’t spent enough time with Circle of the Moon and Aria of Sorrow. I’m a freak who likes all of the DS ones more than Symphony of the Night.
But please pleas please play Bloodlines. It’s tough as nails but it’s such a unique and interesting game. Maybe not as your first 'Vania, but definitely once you’ve tried like, CV1 for a bit.