I started from scratch and completely rebuilt a new VM using the 1171 Windows 10 and Server 2016 template.
There are a few things i did differently on my new built which have seemed to help in my case. I noticed beforehand the logon would be quicker, but that black screen would stick there for like 20-30 seconds in my case along with startup items taking longer to startup.
The 3 things that i looked into.
From HKLM
1. I removed 'Shorten timeout of desktop session switch' from the template before optimizing.
2. I removed 'Enable verbose status messages' before optimizing.
Scheduled Tasks
3. I removed 'Provisioning Logon' before optimizing. I have no clue what this did, but anything that related to 'logon' i removed.
Deleted The StubPath value (not the entire key) from the below locations
Delete HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components\{2C7339CF-2B09-4501-B3F3-F3508C9228ED}\StubPath
Delete HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components\{6BF52A52-394A-11d3-B153-00C04F79FAA6}\StubPath
Delete HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components\{89820200-ECBD-11cf-8B85-00AA005B4383}\StubPath
Delete HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components\>{22d6f312-b0f6-11d0-94ab-0080c74c7e95}\StubPath
I'm not sure if it will work for you, but that's what i've done so far.
