I'm experiencing these issues, too.
I live in Japan, and I just got my new Surface Pro 7 at an electronics store last week.
(sorry for poor English!)
I did not completely solve this problem, but found a way to reduce the symptoms.
In Power Options, selecting "High performance" improves the problem.
However, the Power Option usually only has a "Balanced(recommended)" option.
So, run Windows PowerShell as Administrator and execute the following command on the command line.
> powercfg -setactive 8c5e7fda-e8bf-4a96-9a85-a6e23a8c635c
This creates "High Performance" option button in the Power Options window.
With High performance power plan, the bugs are somewhat improved.
But unfortunately, it is not perfect.
I hope this helps to clarify the problem.
Best regards.