It is like saying fill water in gas tank if you are worried about gas pollution.

If prosecutors are chosen randomly they will little incentive to go after anyone. I think we must drastically reduce the tools these people have at their disposal.

I think prosecutors are elected in the US only as far as I know (even in other common law countries, they are not elected).

In most countries, they are appointed.

that's not really the problem, though, is it? It would probably be better that have prosecutors spend time in different jurisdictions to learn different ways of applying the law.