CV Chronicles will definitely be a challenge to overcome. Rondo on the other hand might not be so challenging due to the fact that there is no whip power-ups. But the harder version of Rondo ala CV: Dracula X (SNES) would be a more challenging run then Rondo. Try killing Dracula in his pillar-floored tower with NO axes to help you.
Take note that Chronicles and Rondo would be completely different challenge runs. Chronicles would be a continuation of the Eternal Candle Challenge, whereas Rondo would be a "one-sitting" no-hit playthrough. Sub-Weapons would still be allowed for the latter.
For Chronicles, I'd probably have to make some exceptions regarding candles since it's impossible to avoid the candles in Dracula's boss room. To avoid destroying the candles, Dracula has to be in VERY specific spots on the playing field AND you have to hit him with a diagonal whip shot to avoid hitting candles. This is far too tedious and unfun to be worth it, and, assuming I use the timer, I'd run out of time long before I whittle down even HALF of his health.
As for Dracula X? I don't really have anything in mind for that game, but of all the castlevanias, that's probably the most reliant on sub-weapons since not only is Richter very slow, but the sub-weapons are incredibly powerful, including the daggers which deal the same damage as your whip (Which was a good balancing decision of you ask me). If I did eternal candle, it would be horrible, but at least I'd get a break in between each level. The "one-sitting" no hit run on the other hand would be devilish considering how hard it is to avoid getting hit. I'd probably resort to equipping the axe for most of it simply due to the invincibility frames of it's item crash (Plus the axe is probably the best weapon in that game).