CS-STAN not that useful for turbine helicopters
Although CS-STAN is definitely a step in the right direction, the devil is, as usual, in the detail. When you review the proposed Standard Changes, very few if any apply to turbine helicopters. For example the Standard Change relating to VHF communications equipment applies to:
Aeroplanes not being complex motor-powered aircraft with a maximum cruising speed in ISA conditions below 250 kts and any ELA 2 aircraft.
This rules out all rotorcraft.
I fully agree that a change to 8.33 spacing radios is a Minor Change on a VFR aircraft. Whether it is plug-and-play depends on the individual aircraft installation and specific radio variants (dash numbers) being exchanged. For example a change from KX165 to KX165a on a twin turbine helicopter necessitated some wiring changes.
I hope this helps.