To be honest that board sort of doesn’t compute with me as its just a usb adapter and its never great through usb.
Command line used: iozone -a -e -I -i 0 -i 1 -i 2 -s 80M -r 4k
Output is in kBytes/sec
Time Resolution = 0.000001 seconds.
Processor cache size set to 1024 kBytes.
Processor cache line size set to 32 bytes.
File stride size set to 17 * record size.
random random bkwd record stride
kB reclen write rewrite read reread read write read rewrite read fwrite frewrite fread freread
81920 4 28410 30628 25668 25728 14916 30629
Cheap Integral 120gb P5 SSD on ASMedia Technology Inc. ASM1053 SATA 3Gb/s bridge and likely you will be about the same.
You can pick up a usb adapter for $5 you can even get them with a 12v barrel and use 3.5" for less than £10.
The m.2 extender and m.2 ssd though will have you much faster. The below post with a evo 970 is a big wow F
Or the will give you x4 ports that are faster, with less latency
https://shop.allnetchina.cn/collections/new-products/products/m-2-pci-e-protocol-to-4x-sata3-0-expansion.
If you already have a Suptronics board X820 then maybe but if not prob better ways.
I am not all that sure how a small inverted heatsink will cope but also check
sudo cat /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_cur_freq
As some of the images are just set to performance with all clocks at max, the debian desktop scales and actually it might just be the ones I have compiled 
sudo apt-get install cpufrequtils if so and pick a milder govenor
I am sort of doing similar but just use m2.5mm pillars to act as ‘case feet’ as inverted heatsinks with heat rising and convection is something that has failed to compute.
I have done something similar but gone slightly nuts on the idea of a Nas,
Got a OMV image that needs some tidying here
You can give it a go but not sure how well those tiny heatsinks will cope.
I just got my RBPi4 delivered today and even on that the passive heatsink supplied is 30mm x 40mm correct way up and it only clocks to 1.5ghz