Why does Dracula's return happen a such random intervals?
This question always bothers me because it's been always clear for me that Dracula returns at quite consistent intervals, but this process can be bypassed through rituals.
1476 - His first appearance
~100 year timespan~1576 - His second appearance. Christopher fails to defeat Dracula and he survives in hiding for 15 years possessing Soleyu later.
~115 year timespan~1691 - His third appearance. Notice how the 15 years were correctly added to the timespan. Simon retrieves his remains and ressurrects him six years later.
~101 year timespan~
1792 - His fourth appearance. Granted, Dracula was brought back by Shaft, but remember how his corruption makes people work to bring him back? This can be one such tool of his to ressurrect.
~106 year timespan~
1897 - Fifth appearance, possibly Bram Stoker's story.
~109 year timespan~
1999 - Julius' final battle.
What I mean is that Dracula seems to be able to return only in dire situations OR after the ~100 years rule~, in which many periods coincide. Notice how the aberrant ressurrection periods happen very shortly after one that would fit inside the rule, and is generally done after Dracula employed a gamble before his death to ensure his early ressurrection.
Aberrant games would be Curse of Darkness, Simon's Quest, Harmony of Dissonance, Symphony of the Night, Portrait of Ruin, Order of Ecclesia.
In Curse of Darkness, Dracula's gamble is to curse the land so the people's anguish can bring him back. But we do see that a very complex plan by Isaac is done to bring the Castle back. Just after Isaac is dead, Death comes in and uses his body to bring Dracula back using the poisonous influence of the Curse within him. Notice that Dracula isn't back until this very point.
In Simon's Quest, Dracula gambles by cursing Simon with a wound on his back. I believe that Dracula knew Simon would try to bring him back to finish the curse, and so saw a chance to kill Simon later, since he couldn't when Simon was at his peak.
Harmony of Dissonance does not have Dracula in it.
Symphony carries on from Rondo. Shaft does all that gamble to bring Dracula back, and that also seems to be a case where Shaft knew all along Richter would defeat Dracula, and thus used it to bring Dracula back later.
In Portrait of Ruin, Dracula IS NOT alive until after Brauner is gone. Death brings him back through unknown means, but I'm willing to believe that this was an "opportunity" case. The Castle was up, Death was there, War and sorrow was raging on, thus Dracula came back. Either that, or having the Castle up brings Dracula back, and this was done by Brauner, who used his magic to have the Castle without Dracula in it. This is the second time Death does this: The castle is up, but Dracula is not there, thus Death goes and uses the opportunity to bring Dracula back at the last minute.
Order of Ecclesia happens somewhere in the 1800's. I cannot think of an argument here beyond the fact that Barlowe also went to great lengths to speed up Dracula's ressurrection.
My opinion is that his canon ressurrections are not as absurd as people make it to be. There are some very specific things going on that explain well how Dracula came back before his time. Specially the "Castle is up but Dracula is not, thus Death can do it".
Why isn't there modern lighting throught the AoS/DoS games; i still break candles for some reason.
Beyond Uzo's point, well... Dracula's castle is something frozen in time, man. It was made to look like a medieval castle, and it probably will always be. On Aria it's his castle, and on Dawn it's a replica (in which the village is possibly not part of the castle itself, adding more to the "timeless" sense when inside the castle itself).
How come Death is able to make a return in many of the CV games but not enemies like Olrox or Beelzelbub?
Death is Dracula's main man, dude. Also, the hero does never explore Dracula's castle in it's full. It's quite possible that there are bosses never fought xD