Get a better power supply, I know prices aren't great right now but that's not a good unit, a 970 would definitely be a risk with that PSU.
You can go with this one :
https://au.pcpartpicker.com/product...ly-modular-atx-power-supply-mpy-5501-afaag-us
Which RTX 3000 are you planning to put in the system? Do you have an approximate budget for the card? I would also agree with getting faster memory, sweet spot for Ryzen 3000 is 3600 MHz, so try to get something around that speed. Do you really think that a 2 TB SSD is a good way to use up one-third of your budget? I would frankly suggest getting a 500-ish GB M.2 and go with a 1 TB 2.5" SSD. Games don't benefit from M.2 storage over a normal 2.5" drive, and 500 GB should (probably?) be enough for the other tasks you do that might benefit from this. You could also go for 1 TB M.2 and 1 TB 2.5", that would probably still be cheaper.
Do you have a specific reason for going with a Mini tower case? If not, I would suggest getting a mid-tower since it gives you the option to get an ATX board as well, just a nice additional compatibility feature to have.
With these changes, these are the parts I ended up with, actually spending LESS than what you were and getting better components, mainly due to the storage being cheaper, allowing better components in other areas:
PCPartPicker Part List
CPU: AMD Ryzen 5 3600 3.6 GHz 6-Core Processor ($289.30 @ Newegg Australia)
Motherboard: MSI B450M MORTAR MAX Micro ATX AM4 Motherboard ($166.60 @ Device Deal)
Memory: G.Skill Ripjaws V 16 GB (2 x 8 GB) DDR4-3600 CL16 Memory ($135.30 @ Newegg Australia)
Storage: Samsung 860 QVO 1 TB 2.5" Solid State Drive ($155.00 @ Centre Com)
Storage: Intel 660p Series 1.02 TB M.2-2280 NVME Solid State Drive ($199.10 @ Newegg Australia)
Case: Thermaltake Versa H17 MicroATX Mini Tower Case ($59.00 @ Centre Com)
Power Supply: Super Flower Leadex III Gold 550 W 80+ Gold Certified Fully Modular ATX Power Supply ($159.00 @ PCCaseGear)
Total: $1163.30
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2020-07-13 12:03 AEST+1000