I gave up on Rx5700 today and went and replaced it for an ASUS RTX 2060. Works right out of the box. Scored 5X on the Unigen Heaven benchmark test. No issues with playing youtube videos. The system seems to be at ease and seems to be working much better now. I guess a stable/mature video card with established drivers is the way to go. I couldn't wait for AMD to get the drivers right - lost my patience after 2 weeks of playing install/uninstall drivers.
This is better for GPUs https://benchmarks.ul.com/3dmark#windows
My rig is similar to yours and hits 7600, which according to 3D marks scores is decent. But, the performance in some games, Destiny 2, for example, is below par. I'm returning my 5700 and getting a 2060 GTx. Never had so many issues trying to get a card to work. Truly atrocious.