Faster hard drives will definitely improve PD11 performance, in my opinion. I have twin 600 GB WD Velociraptors in RAID0 array as my Drive C:\ and have a Hard Disk Windows Experience score of 6.2, my bottleneck. All other indicators are 7.8 or 7.9.
I considered purchasing an SSD when I configured and ordered my current computer (see signature) about 18 months ago, but the SSDs were pricey, smaller capacity, and the hardware gurus here indicated that the SSDs of the time might not play nicely with PD11, which writes temp files to the OS drive when rendering.
Certainly if you wanted peak Hard Disk performance, I would not get less than a 250 GB SSD as my primary drive, and then have a second standard hard drive on which all possible programs and data would be installed, to leave as much of the OS SSD drive free as possible for PD11 temp files. Some recommend having 50 GB free for HD editing; some claim 100 GB free will lead to peak PD11 HD performance. I don't claim to know.
Today, I might make a different choice as SSDs have grown larger, more reliable, and less expensive.
Just my two cents. Have a great day.
Regards,
-Phil
Windows 10 Pro x64
Dell XPS 8930
Intel CoreT i7 (4.6 GHz)
32 GB DDR4-2666 RAM
1 TB PCIe -x4 SSD
NVIDIA GeForce RTX 2060
PD14 Ultimate x64, 4207
CD4 Ultra and AD6 Ultra
Bleeping Computer Malware Response Instructor