A shame, too, because AMD’s cores and performance would really kill it for you for your tasks. 
If only Autodesk would support AMD more! The heat issues–I understand your complaints, by the way, it has been mine for so long (long time AMD user lol), but with Ryzen it isn’t like before–have been so drastically improved it isn’t a problem anymore.
As for your build, I think it would really help you for your needs to try and push for an i7. The Intel Core i7-8700K would do you wonders, and last you longer. Other than that, I agree with Pylinaer about dual channels but if you plan to upgrade later,keep it like that. However, there are kits you can get for the same money that gives 16GB still and have better latency.
https://pcpartpicker.com/product/p6RFf7/corsair-memory-cmk16gx4m2b3200c16
($79)
Beyond that, solid build for sure! 
(Oh, just want to mention that Seagate offers its latest model of 3tb HDDs, 7200 RPM (6 Gb/s 64MB Cache), for around $79 in case you might be browsing about for 'em still.)