I'm sure there's a lot to this, because whenever I paddle with flat water kayakers, I always notice how clean their catch is and how much I slap the water even though I'm concentrating not to do that.
Hope someone will give some insight into this
Current: Carbonology Boost double, Jantex Gamma Mid
Previous: Nelo Ocean Ski L, Jantex Gamma Rio Large Minus
Turbulence on catch= your blade is not anchored and you are limited in the force you can apply to move yourself past that blade. Distance per stroke suffers.
Turbulence on exit= likely means scooping water which slows the boat right at the moment it should be moving the fastest. Distance per stroke suffers.
So yes, quieter is better. There are many ways to err, so hard to troubleshoot on a forum but if you have an idea of what good form should feel like, you can experiment with the different components and see if it feels and sounds better.