Well, Kropotkin agrees with you in the last regard; that power should not be concentrated at all.

What he favours is a system such as yours, but differently. Trusts, which are inherently money-based, would be meaningless under an anarchocommunist system, as there is no money to speak of. A gift economy is one option, in where goods are directly given to one another without expectation of reward, and without a middle man such as money.

To prevent a "free rider" or "hoarder" problem, a pay-it-forward model could be handy, in where if you want goods, you need to give plenty back to the community.