The representatives will, in practice, make decisions under the system you're describing.
It was called the "spoils system" (http://en.wikipedia.org/wiki/Spoils_system), it turns out to be a major vector of abuse by elected officials, and is the reasons the US civil service has safeguards for dismissing civil servants.
Sorry - you don't get to hide behind representatives.
> I believe there's already a commonly applied differentiation between appointed and civil service[1] positions.
While there is a difference, the "you can't do things that piss off the voters" rule applies to both.