Feature: Show Tooltip semi-permanently while typing parameters
I would like a setting that would let me keep a tooltip visible for the command (or method) signature that I'm currently typing, like this:

Right now I can get this tooltip by typing Get-C{Ctrl+Spacebar} and then typing h:

But when I accept the completion or start typing more, the tooltip dissapears, so I can no longer refer to it.
Expand upon this by showing the relevant content for the part of the cmdlet being typed. So on a parameter, it should show possible completions, but after a parameter is complete, show the input type and possible minimal help on the parameter. For .NET API usage, show overloads, types for parameters, etc...
This is sorta addressed with tooltips in ListView of PSReadLine 2.3.4 and the Completion Predictor.