First Time Setup - Hardware Check

So let me start by saying that I am new to Unraid and my experience with it is basically limited to the Linus Tech Tips videos and a couple of SpaceInvader One's install and setup videos. I have not setup Unraid yet because I am trying to decide what hardware to buy and that is the purpose of this post.

 

That said I am wanting to create a setup for the following purposes in order of priority

 

1. Everyday Windows 10 usability with the ability to do a lot of gaming and some CAD work

     - I'd like to have my games on an SSD for better performance

2. NAS and Plex Server (the NAS will be accessed by the VM and two other PCs on the network)

3. Maybe play around with a Linux VM

 

The hardware I currently own is:

Asus Prime  X470-Pro

Ryzen 7 2700X

32 GB (2x16) Corsair 3200Mhz DDR4 Ram

MSI GTX 1070 Ti

 

Storage:

1 x 4TB Toshiba 7200 RPM NAS Drive

2 x 1TB older HDDs

1 x 500 GB Intel SSD (about 4 years old and where my OS is currently installed)

1 x 1TB Crucial MX500 SSD (A couple of months old and currently is the one I use for a game library)

1 x 265GB Crucial BX500 SSD (The drive I was using for the OS on the FreeNAS machine I had running)

 

The hardware I am going to get: 

Ryzen 9 3900x

an additional 4TB Toshiba NAS drive for my parity drive (I may buy more and add to the array in the future)

Graphite 760T ATX Full-Tower

 

Hardware I was potentially going to get:

2 x SansDisk Ultra 3D 512GB SSDs (for the cache)

1 x WD Black NVMe SSD (For the Windows 10 VM OS install)

 

My questions then are:

1. Am I going overkill on the SSDs? I didn't realize until recently that you can just use part of the cache drives for the VM OS install and leave the remaining for the cache but won't this increase the IO on the cache drives?

2. If I want a game library to be on an SSD should I have one of them setup as unassigned device?

3. Basically, given my use case and the hardware I'm considering, how would you suggest I split up my drives (parity/cache/unassigned devices/etc)?

 

If you see any assumptions I've made that are incorrect let me know too! There is definitely a lot to learn but I am committed to figuring it out. Any help is greatly appreciated.