After Simon's Quest there seems to be another game taking place every 50 years or so (OoE is unclear, but following the trend I'd say it's probably mid-1800s), and 3 times in a 50 year period between Bram Stoker's novel, Bloodlines, and PoR.
The early years are much, much less cluttered, with at least 1 full 100 year resurrection (Belmont's Revenge to the original Castlevania), and ~97 years between Curse of Darkness and The Adventure. Though, personally, I'd like to keep it this way.  It would be pretty disappointing if the "every 100 years he has a full resurrection" thing never happened.  Though I've never been clear on if the 100 year cycle still brings him to full power even if it's been interrupted by premature resurrections.
Either way, my guess is they'd probably stick to the 1800s, maybe use the premature resurrections and lack of full power as an excuse of sorts for how non-Belmonts seem to be doing just as well against Dracula as many Belmonts did (Well, and almost all of them so far had help.  And the vampire killer ritual.).
If we're going Dracula-less side stories, then there are a ton of opportunities.  I don't know how others feel about it, but I wouldn't mind a side story explaining what the Belmonts were doing in their 200 years without the whip. Though I think I'd be happy just to have a new game.