Having flown skydiving ops in both a C182 and a C208, I can make a few comments. First in the C182, the practice was to descend with cowl flaps closed, the throttle retarded but not at idle. "Clearing" the engine was done, and typically I would use a 50 degree (plus or minus) turn to maintain situational awareness and to increase the induced drag, and descend quickly.
In the C-208 the operation was similar, except that power was brought back, and there was no clearing of the engine, as it is meaningless with a turboprop.
On both aircraft I would frequently descend with full flaps. I did not use Vne descents, as often the air was not smooth, and the full flap descent at a lower speed offers adequate visibility and a steeper descent than just Vne.
The C182 was not turbocharged, and I know of no one in the area who uses a turbocharged recip for skydiving, although I am sure there are people who do elsewhered
Also, in the C182 normally there was a few minutes of flight at reduced power (75 or 70%) while ATC was contacted and the jumpmaster got happy with the traffic in the area, and where he was WRT the dropzone. This allowed CHT to drop more gradually.