You've assigned 8000 mb ram to every single plot, I would give them 4000 mb each, that's enough
From my tests I didn't see much difference using more and in addition to that if all 12 plots are running, you are using more ram than you actually have, even though plot manager doesn't use all the ram you've assigned to the job all the time.

Check if your global settings are interfering with your job settings (like max_concurrent:)

Check out the copy time in your log files at the bottom, add 5-10 more minutes to that time and use that number as your stagger_minutes.
You can find the log settings almost on the top in you config.

If you are not doing any much demanding tasks while plotting do this:
enable_cpu_affinity: true
cpu_affinity: [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 ]
This uses 10 cores (20 threads) and leaves 2 cores (4 threads) for other tasks.

Optionally you can change the windows_process_priority to 256.

Stop raiding your SSDs, afaik if you are doing it with software and not with hardware, it slows them down.
Use them seperately and start 2 jobs with each one.
If you do that you will have to go "minimum_minutes_between_jobs" in your config and change the time to your stagger_minutes which you've found by following step 2.