The current state of Konami makes the prospect of new Castlevania game (at least, one not centered around "erotic violence") unlikely for the foreseeable future. There's Bloodstained, of course, but it's not quite the same.
But soft! Even if you've played every Castlevania game to date, chances are pretty good that there are a few classic Konami adventures you've missed that will scratch your vampire-hunting itch. The Shaman King: Master of Spirits duology for Game Boy Advance is essentially Castlevania in all but name — and while they don't stack up to the superlative Aria of Sorrow, you could do a lot worse than hunting them down.
Shaman King, if you somehow (understandably) missed it, was a somewhat short-lived manga and anime series that Konami optioned for video game spinoffs. While most of the resulting releases turned out to be pretty forgettable, the Master of Spirits games transcended their source material and the curse of handheld anime-based platformer mediocrity. While Master of Spirits didn't share any staff in common with their GBA Castlevania contemporaries, the two games seemed suspiciously familiar, with visuals and mechanics that felt ripped straight from their more popular Konami siblings. The spirit-collecting system at Master of Spirits' heart was more than slightly reminiscent of Aria's Tactical Soul System — though, interestingly, the first Master of Spirits actually predates Aria by about a year. If anything, it would seem Aria owes a creative debt to Master of Spirits.
Neither Master of Spirits offered revolutionary gameplay or design or anything, but both were solid examples of their genre with a strong spiritual connection to a fellow Konami franchise. They remind me of a holdover from the 8- and 16-bit days, when Konami would take a media property and lavish far more love and care onto it than they had any right to. They're no replacement for a true future for Castlevania, of course, but it's a decent enough substitute in a pinch.