Cv3 not rondo.
Dracula's Curse IS IGA's favorite, but RoB is ONE of IGA's favorites. Er, at least in his top three. IGA said CV3, RoB and CV1 were his top faves out of the series.
And regarding non-Belmonts vanquishing Dracula, from the non-Belmonts we have, I wouldn't take them too lightly. It's not like they are random people. I recall hearing that Hector's dark powers originate from Dracula himself, hence only a Devil Forgemaster is fitting for a vessle to Dracula. That being said, Hector was considered the superior vessle, Issac the inferior. Out of desperation Isaac was used when Hector shook off the darkness that overcame him. I would think that would be a world of difference. Dracula was brought back through an INFERIOR vessle, which I'd think only made it easier for Hector to defeat him. Perhaps of Hector was used as the vessle, Dracula would be more stronger(so strong that only Trevor could match him in strength).
Also, Alucard, the other non-Belmont hero. He's the son of Dracula. I'd think he'd prove to be strong enough to take on his father.
Who else, the Morris clan? They're Belmont related. Perhaps IGA made them less powerful than the main Belmont line, but they still have enough power to wield the VK whip, even if it drains their life. I wouldn't think any normal person, at the least, could do that. The VK would probably drain their life in an instant.
And we still don't know WHO Shanoa really is. When a designer makes it a point that she has a codename, her true name is vital to the plot.