with nearly 30 years of archery I do not think window riser is important

Center cut riser facilitate the choice of a spine That is sure .Nothing else

Regular training will bring your brain to an habit where accuracy is independent of your hardware

Key is training , nothing else

In another area I know very well ( IPSC)trained shooter is better with a gun out of the box rather than an amateur with a high quality weapon, even if prepared by best gunsmith8)