Start process with low priority, NOT modify directly after start.

There are many examples to modify a process priority via powershell. All those examples have in common: start the process and then, AFTER it is started, set the priority.

Typical (abridged) example:

$proc.Start();
$proc.PriorityClass = [System.Diagnostics.ProcessPriorityClass]::Idle;

Is there no way to start a process directly as low priority instead of modifying it after start? Or do I have to use the ugly "start /low powershell -file" method since Microsoft forgot that within powershell?