I love RPG's, but only when they appeal to what I look for in a game.
Otherwise, they tend to bore me.
That being said, my favourite games ever not counting Castlevania are almost all RPG's (or kinda)...
Radiata Stories, Valkyrie Profile 2, Star Ocean 3 and 4, Final Fantasy 3, 4, 6, Valkyria Chronicles, Chrono Trigger, Vandal Hearts 1 and 2, Eternal Sonata, Grandia III, Tales of the Abyss, Chocobo's Dungeon...
And other favourites also have a lot of RPG elements...
Okami, Twilight Princess, Gargoyle's Quest II, the Metroid series, Alundra, Demon's Crest, Act Raiser...
Also, my favourite type of Castlevania is MetroidVania, because of the same reason: the RPG elements, exploration, leveling up, items, etc...