[Darryl Ramm]

You can guess the size of the audio in your sessions and set the disk cache to that, then look at the disk cache meter as sessions load. The reference guide has an explanation of that meter. Now does this really help you or not… if you are not having any AAE errors it may not, if you ever see an error, make sure you are giving Pro Tools time to load the session—ideally fully cached with the meter turning green.

Sounds like you mostly have a disk space issue, but with those drives and disk cache you should have the flexibility to put stuff wherever you want for space/convenience/workflow/backup reasons without worrying about drive performance.

Now if VI performance or startup times are issues you might switch between streaming and caching samples if the VIs support that, or increase/decrease their memory size. But basically on modern systems I would just install stuff in the easiest/most convince them way for you and then see how it goes. The old rules about dedicated audio drives are thankfully long gone (but you might still go that way if convenient for you).