Needs a robust interactive help
It really needs some sort of interactive help option that can be turned on where it gives the user a heads up display of what options are available and what arguments, if any, are required for the command... Sort of like how VBA for Office worked or the Visual Studio editor... Complete with a mouse hover detailed description and links like the normal Windows Help has...
The normal Intellisense and tab completion in PowerShell ISE is not enough? There is also the "Show-Command" sidebar, which you can run from a normal PowerShell console too.