Not quite. What I'm more alluding to is something like, say, rewriting smss.exe and csrss.exe to be CLR programs (along with the implication of porting the CLR

Not quite. What I'm more alluding to is something like, say, rewriting smss.exe and csrss.exe to be CLR programs (along with the implication of porting the CLR to the Native API) and giving PowerShell access to their internals directly.