Honestly my biggest complaint is just that it's more verbose than bash which is admittedly pretty cryptic at times. Now that I've learned bash though, I have little need to move to PowerShell.
Bash is tough to learn at first because its syntax is alien but I've learned enough to get things done with it.
I wouldn't call it over-engineered. Ambitious? Maybe, but I don't see PowerShell lagging behind in any front it's designed for.