It doesn’t matter where you put the Cubase application itself, at best you may improve start up of the application by a few seconds fwiw.
For the content if you use it then faster drive etc. will improve load time (of that content) quite a lot.
For other libraries that you may wish to use that stream samples in real time etc., again faster drive will help.
Use your fastest drive for your current projects / audio etc.
Even if you only have small external SSD for example, use that for your current project and move unused projects to a backup (to create space).
Obviously in an ideal world, all your drives would be at least SSD (I have 6 here and many folks will have even more).
So my list above is kind of ordered from least important, upwards.
It is easy to advise you to move everything to faster and more recent and expensive gear haha.
This is why I gave a list of priority above.
So again, if you are going to go m.2, just one for projects will help you for sure.
I always use the latest available versions of anything tbh and have never had an issue. But I am used to testing and troubleshooting and of course, daily DAW housekeeping.
(I haven’t moved to W11 yet purely because of my current system.)
I have been creating studio installations for some time now. Here are a few tips for setting up audio and video workstations (these work for both):
Keep Steinberg applications, project files, and audio content on separate drives (so three drives total).
Use only SSD or M.2 drives. M.2 is great for applications. If you still have HDDs, use those for content storage, not for projects or apps.
Leave adequate free space on your drives. As an absolute maximum, drives should be no more than 2/3 full, but it’s better to keep them at half full or less. Plan ahead and account for the fact that updates to projects, applications, and content will fill up space over time. A good rule of thumb is to always allot twice as much space as you think you’ll need. Anything under 2TB is likely inadequate. Remember that installation time and cost are greater than just the drive cost.
Never use multiple partitions on a single drive, especially for audio or video production. Keep projects, applications, and audio content separate. VSTs would be part of the applications drive, while VST content (samples) would be part of the content drive.
Think of the SSD as a city with a single highway going in and out (the I/O). If too many people live in the city, that highway will become a bottleneck very quickly. No matter how good your graphics card, memory, or CPU, HDDs can still bottleneck the system, especially for real-time DSP applications. You need multiple fast highways to keep things flowing smoothly.