They accomplish different things. The Bokor C3 - Pardoner C1 - Plague Doctor C2 so many people are trying out is a solo build that doesn’t play well in parties compared to other builds, and also has a hard time against high magic defense elites.
Bokor C3 is also largely unnecessary if you don’t plan on playing with Damballa, as the Mackingdal duration increase is negligible for another circle and the Effigy multiplier bonus can also be considered too steep a price for a whole circle. You can however pick Bokor C3 if you want to save money on attributes, but I think that planning short term is dangerous for long term characters.
Cleric C2 - Bokor C2 - R5+6 - Plague Doctor C2 is core for the generic solo KR build. Pardoner is not necessary with the exception of Plague Vapors upkeep, as everything else has 100% uptime with ease. Those two circles are open for play. Pardoner C1 is only popular in Korea because it was a good pick with only seven circles open. It’s popular going into R8 because very, very, very few KR players are willing to re-do their build just for trying out some other option. It’s mostly a pigeon-holed popular pick. It’s still a good pick, but it’s not mandatory to complete the build going into R8.
This gives you some options to take various jobs with different assets that can determine what you can contribute to a party. Pardoner C1, Priest C1, Miko C1, so on and so forth. It really depends on what you want to be able to do for certain situations, beyond just solo play.