Advice on OTiS build (NAS, NZB, Blue Iris)

Hi - firstly thanks for the fantastic website…

I currently have been relying on an old Synology DS418 as a NAS and separate PC build to act as gaming rig and server.

I’ve recently been putting together my own short depth server rack (12U) which mainly houses Ubiquiti UDM-Pro and Switches thus far… I have had on pre-order a Synology RS1221+ but it keeps getting delayed and I then came across the alternative Unraid DIY. I am pretty attracted to this idea since the Synology would have insufficient power to meet my needs so I would have needed a separate NUC anyhow for yet more cost.

Main uses being sought:
Unraid NAS (as much storage as possible but 4 16TB drives in an array + 1 2TB SSD for OS/cache should suffice)
Plex server running on Ubuntu container
NZB, Sonarr, Radarr, Lidarr, Home Assistant on Ubuntu containers
Blue Iris + general workstation (via HDMI to monitor) on Windows container

Current hardware I am thinking of:
|Case: X-Case XG430D - 4U 300mm depth|
|PSU: Be Quiet! Straight Power 450w 80plus gold|
|Motherboard: Gigabyte Intel B365M mATX|
|Processor: Intel Core i5 9400|
|Heatsink: Arctic Alpine 12|
|GPU: Zotac 1060 Mini 6GB|
|Memory: 2x Crucial 16GB DDR4 2666 Dual Rank - CT16G4DFD8266|
|SSD Storage: Sabrent Rocket 2TB NVME M2 Gen 3 2280|
|HDD Storage: WD Red Pro 16TB x4|
|NIC: Mellanox ConnectX-2 10Gbe|
|Fans: 2 in case already (120mm+80mm) but have 2 Noctua NF-A8 PWM (80mm) also I thought I would use for the Synology|

I am afraid I will be told I am crazy thinking this can all fit in that case safely etc but some general questions I had:

MB: should I consider ATX rather than mATX - just concerned re space
HDD: I see a lot of mention of SAS adaptors - does this make a big difference versus Sata 3 in reality?
The case description seems to suggest it can take at least 4 3.5" drives and 1 M2 SSD which I think should work the motherboard
HDD - I see a lot of mention of WD Reds on the site - would it be worth considering the much cheaper EXOS 16TB drives (I think Gen 1 is Sata 3)? (I tried Ironwolf Pro in a synology once but they were clicking every few seconds which drives me mad vs a general hum!)
GPU - to use the server with a windows VM as a desktop as well I believe I need a separate GPU to pass-through or could the I-GPU suffice or would that already be allocated to e.g. Plex server transcoding? Advantage of 1060 is this could be used for light gaming still on the workstation I guess
CPU - I want a decent processor given various roles the server will play but should I consider e.g. the i5 9400T vs i5 9400 given lower TDP?
Case - would I be better off getting a smaller 3U case if possible and then e.g. a separate 1U case to hold HDDs and therefore externalising them?

Any other suggestions / comments much appreciated… no offense will be taken!

What you end up with and if you will change something?

Hi - yes, I changed it quite a lot in the end - ultimately decided this is not something I will be rebuilding frequently so pushed to get the best overall performance I could achieve within such a confined space - and I must admit it is working delightfully thus far with Unraid/Plex/Windows VM and a lot of dockers.

Final hardware specs I ended up with were as below - happy to answer any queries etc

Case: X-Case XG430D from x-case.co.uk - went for this since 4U 300mm, takes full-size PSU, supports up to 5 3.5" HDDs (4 really) and has 7 expansion card slots. Did require some minor mods to get it all to fit.

PSU: Seasonic Focus GX 550W Power Supply

Motherboard: ASUS ROG Strix Z490-H Gaming Intel Z490 LGA 1200 ATX Motherboard - spent a lot of time researching given importance of expansion slots for any server build and this ultimately gave me 5 extra slots and 3 running at I think 8x - also the BIOS configuration seems pretty detailed and allowed me to configure everything to be working very stably (like GPU passthrough etc). Main fun was getting the USB to boot into unraid - ultimately, was not able to achieve this without UEFI and a few other settings tweaked.

Processor: Intel Core i7-10700 - chose this for both Quicksync but also optimal performance whilst limiting to 65W

Heatsink: Noctua NH-D9L: - ultimately was the best cooler I could find that would fit height-wise - am not trying to overclock and it also doesn’t impede on ram slots etc

GPU: Palit GeForce GTX 1660 6GB StormX GDDR5 - having initially been sold a dud 1650 on ebay (it had damaged video ram so would work but crash whenever put under load - took a while to figure it wasn’t an unraid passthrough issue!) - I then decided to maximize performance for the case and this is pretty power efficient whilst being much more capable than a 1650. It only just fit though because the power connector attaches vertically at the top! (need a right-angle adaptor)

Memory: HyperX FURY RGB 32GB (2x 16GB) 3200MHz DDR4 RAM

SSD Storage: 2x 1GB SSD WD WDS100T3X0C-00SJG0

HDD Storage: 4x MY BOOK V3 18TB BK EU - super easy to shuck with guitar picks and worked immediately

Flash drive: SanDisk Cruzer Fit 16GB USB 2.0 Flash Drive - micro, usb 2 and attached directly to motherboard usb expansion port with a StarTech.com USBMBADAPT

NIC: Mellanox ConnectX-2 10Gbe

Additional expansions cards: Inateck Superspeed 4 Ports PCI-E to USB 3.0 Expansion Card - for passthrough to windows VM

Other: put an extra couple of small fans into the case wherever could fit to aid air flow and installed a second m.2 heatsink cooler since only one slot comes with one by default (not sure makes much diff though)