Assuming that your posted drawings are scaled, allowing space for plumbing, the largest angle that you will be able to achieve is about 5 degrees from vertical. This should be sufficient.
Minute grooving may provide more turbulence. Grooving that is too deep, however, could cause problems with splash out.
How are you planning on disguising/hiding the overhead water supply pipe?
"Everybody is ignorant, only on different subjects." - Will Rogers