Renting out capital doesn’t imply taking a portion of someone else’s labor. They are just paying for a segment of the capital services, which are an input to the production process. The input-maker has to get paid. Selling the capital is just selling all future capital services.
There are ways to bake in anti-wealth-concentration measures into a currency like a fee on holding the currency.
Economic planning doesn’t work, and is incompatible with workers’ self-management.