Personally I loved Aria of Sorrow. I enjoyed every single second of it. I think the plot twist was very creative, about how you were playing as the reincarnation of Dracula all along without knowing it. The levels and backgrounds were beautiful - especially the first one where you could see bats flying around in the background etc (I fall easily for minor graphic details). Plus, character designs were great and the spriting as well. I can understand though that picking a japanese teenager wasn't the ultimate choice, but I still have nothing against Soma Cruz. IGA also managed to place a Castlevania game in the future and still make it great. The whole thing felt new and creative, just like SotN.
Unforunately they created nyappy-neko-chan Dawn of Sorrow and turned it into something you could see on Disney Channel. I'm sure Ayami Kojima was busy, but a blank cover would've been better than what we encountered in it. Sure, I know it's not just about the artwork, but it kinda felt like all the characters changed personalities. Hammer turned into some love-crank wuss and Alucard wasn't as ''mysterious'' as he's usually been. And Soma looked like something you could find back in the 70s. Sorry for nitpicking, but I'd say DoS is the worst Castlevania title.
As for the actual topic; YES I think IGA should stay. I agree with the fact most of you say, that it's getting a bit too predictable and it the Castletroids are getting too overused. They should take some time off with Castlevania and give IGA some time to come up with something REAL great. Something new and creative, and perhaps give him a better budget too. They should give him time and a budget for an ultimate 3D Castlevania game. IGA's the one to do it. He probably just need some time to refresh his talent.