[epsylon]

> I find PowerShell a delight to script in, but terribly cumbersome to use interactively.

That's because you can't be both! The shell wants to be both an API and a user interface, and these are two goals that are fundamentally at odds. An API should be structured, strongly-typed, unforgiving; a UI should be discoverable, intuitive and unconstrained by the needs for automation or programmability. Programmers are stuck in the idea that a command-line shell running in a terminal emulator (emulating hardware from the 70's) is the pinnacle of interaction design, which is extremely sad.