Hi Guy’s I am having the same issues with very slow rendering times on a 2 minute video. I have done some tests and came to the same conclusion as you that color director has some very serious flaws. Here is my PC spec.
AMD Ryzen 7 3700X
MSI MPG X570 Gaming Edge Motherboard
Nvidia GeForce RTX 2060 Super Windforce 8MB
Corsair Vengeance LPX Black 32GB 3600MHz Ryzen Tuned
I work off a M.2 ssd 250GB drive
I have run these tests and the results are surprising, here are a few setting i use in Prefrence Settings. Under Hardware Acceleration i have (Enable Nvidia Cuda Technology to speed up video effect preview/render) ticked. and (Enable Hardware Decoding) ticked. Under Produce i have (Render Video Blocky Artifacts) ticked and (Reduce Video Noise when using MPEG1 MPEG2 and H.264 encoders) ticked, the other 2 under H.264 AVC are unticked.
So Test One is a 01.51 length bare clip with Hardware Video Encoder on (SVRT is grayed out) and the render time was 00.31sec
Test 2: As above plus 4sec Basic title with a 2 color gradient, render time 00.36sec
Test 3: As above plus Effect (Conjure Right) and fade, render time 00.36sec
Test 4: As above plus End title, 2 color gradient and Fade, render time 00.37sec
Test 5: As above plus Fade in/out effect on main clip, render time 01.37sec
Test 6: As above plus main clip time reduced by 41sec (done in Video Speed Designer) render time 00.43sec
Test 7: As above plus Color correction done in (ColorDirector) A little Exposure and Contrast on the + side A little Brightest, and Midtone on the - side Clarity and Vibrance on the + side and in the Saturation Channel Magenta and Green on the + side. Render Time 07.37sec
Test 8: As above plus an MP3 track form Epidemic Sound with a 8sec Fade Out, render time 07.35
As you can see there is not much difference from test 1-4 it goes up a bit in test 5 by 1 minute and in test 6 the time is down but this is probably due to the video now being 41 seconds shorter.
Now test 7 is where we see the big difference, render has shot up by 7 minutes 6 seconds, so it seems to be the color correction in color director is the thing that’s slowing things down dramatically, and in test 8 for some strange reason after adding a music track the render time goes down 2 seconds.
I also have done the same test in Davinci Resolve 16 free version and it rendered the video in about 1minute 45sec a huge difference. I used to use davinci but could never get use to the color wheels, scopes etc, I took out the powerdirector 18 365 subscription because lots of people were recommending it because of its speed, I’m feeling kinda cheated now.