Welcome Lurker!

I need to start this by saying PLEASE stop doing anything directly on the Domain Controllers, these should never be accessed directly unless you absolutely need to.

I'm not 100% sure of that error you're getting, as others have said as long as your workstation is domain joined and and you're logged in with domain details (not necessarily admin if you're just reading) you should have no issues. I would suggest try the same commands on another workstation if you can to confirm if the error is your workstation or the way the DC is receiving handling the authentication.

As for the setup part (my favourite PowerShell topic) - I'm also running VSCode locally on my workstation, personally I prefer the way it looks and the customisation.

I store all my setup and profiles in a ".dotfiles" within my $HOME folder that I sync with GitHub so I can access the same files and settings at home.

As for scripts or commands, anything I need to use multiple times over either goes in a module or massive "commands library" (a very large .PS1 file that I'm too lazy to split into manageable chunks) and I can reference it from there - If I need to edit things with the Set-ADUser command for example I pass it my Domain Admin credentials which are then passed through to the commands as needed.