I've found that the $HOME variable can be rather useful for keyboard-only navigation in PowerShell. It would be nice to have a number of shortcuts stored as persistent path variables that can be accessed using the same syntax. I've seen the method $env:MyTestVariable = "My temporary test variable." but the result isn't persistent and still has to be accessed by typing $env:MyTestVariable which is not as succinct as the desired $MyTestVariable.
How can I create such variables and control what level has access to them (aka User, Machine, and Process)?