hey eric
regarding the 3 images, C/D i like the best.

1 
to evoke the meditative state whilst looking at the image:   
A - water and reflection is the best idea for evoking the meditative state. however the overuse of yellow colour  in mass, wipe out that advantage.
B - the  silhouetted pines in a spear , sharpish shape - not conducive to  the meditative state. 
C/D - yes, observing the beautiful swirling sky  can be conducive to the meditative state. and importantly, the direction of the mist, guiding the eye and spirit from earth to heaven.
2 
regarding the artwork of the cover itself,  before consideration for the subject matter,  ie artistically speaking: 
A - too much yellow in contrast with green - kind of. bilious-making. A perfectly balanced image/text and mass/tone in relation to the text also, perfect.
B  - colours of sky are too wishy-washy. too many elements, filagree black edges from the silhouetted pines, and wispy colours where there needs to be more solid colour.
C/D - the contrast is right, the balance of text to mass and  tone is right. (one can enter the meditative state by many paths. one of the ways is to look at a perfectly harmonious artwork. - i choose C/D)
C and D appear to  be the same,  if C is more contrasted than D, then CCC.
if  C and D are the same, C & D.

if the colouring in A was better, little if any yellow and less dark green to begin with (the greens and blues in the sky  of image C/D are far more harmonious and peaceful and pleasing) ....  then i would have chosen A.

cheers from mim