Are you familiar with potlatch society in the old Pacific Northwest? With wealth readily available, the "big men" of a tribe (roughly chiefs, but not hereditary) competed to see how much they could give away to their neighbors and rivals; all you had to do to eat well, or make it through a bad winter, was to admit that your neighbors were led by a great and glorious chief.

This system didn't work very well at the time (it bred slavery and warlordism, and produced a lot of waste, especially towards the end, when trade goods were abundant and population was running out); but it'll become increasingly more doable as capital becomes more productive. Magnanimity is a human instinct, and people already compete on status and prestige; just persuade holders of capital that supporting the unemployed/unemployable is a good thing, make sure they get personal feel-good-ness out of it, and persuade the unemployed/unemployable not to run up the red flag, and you've probably got a stable system.

Probably. I don't think we need to worry about slavery much, but warlordism could become a serious issue. Where potlatch-like culture exists, aggressive bids for the throne (or equivalent) tend to follow; the Earl of Warwick in the War of the Roses comes to mind. Still, even warlordism has potential to be less bad than Communism (more room for ambition, better management of capital) or Fascism (you can be a minority and not die) -- the Wars of the Roses had roughly zero impact on the common people of England. (See A Farewell to Alms for a detailed discussion of how England's wars, starting from a pretty early date, avoided messing up England's people.)

This is all hypothetical, though; I'm not saying that a potlatch orientation is the only possible solution, nor even that it's necessarily a working solution at all...