Is there any good ideas on a plausible way to manage power? The fundamental laws governing power, politics, wealth etc seem to always lead to negative outcomes.

Like state socialism led to the same complete concentration of economic power in the hands of the few as late stage capitalism is doing now. But I’ve never heard of any plan to address this.

Generally, the suggestion is either "Separation of powers" (ensuring that each power-hungry institution has a self-interest in keeping the other power hungry groups from getting too powerful) or decentralization of power (a la anarchists). Both have strengths and weaknesses. State socialism in most polities has only been attempted with very... authoritarian regimes with no real interest in separation of powers (and certainly not in decentralization), so there's some ambiguity as to whether it would work out better in a legitimately democratic polity.

One idea would be to randomly select representatives, bypassing filters that select for those who are best at accumulating power at the expense of anything else. Randocracy?

Sortition, that's called. The ancient Athenians used it for some offices.