Doesn't N-Rage provide a rumble feature already ? Why bother with another one ?
By the way, if you are working on Castelvania, make sure you do Castlevania - Legacy of Darkness, it's the follow up of Castelvania 64, but it's more like a director's cut, where several things are fixed(gameplay wise) and a few levels remixed, but in spite of a different start the game is pretty much the same, when you are done you might even re-use the same texture for Castelvania 64!! And it would be nice to play this game again, it's being said that this game wasn't worth to have this name, because it doesn't really capture the spirit of a classic Castelvania game, but I enjoyed it never the less.