[sprucevoid]

Yes to per-person guaranteed income. No to flat income (or wealth) tax (progressivity is better so no good reason to switch to something worse). Revenue neutrality: only if, and to the extent, it makes it makes the policy package easier to pass.

[hedora]

In practice, progressive tax curves and incentive programs let politicians meddle. Once they can meddle, lobbyists write the tax code.

So-called progressive taxes are always regressive in practice, at least in the US. Keeping the math simple makes it easy to keep them honest. (Make the marginal rate 40-50% if you want. Just set the base income so that the middle class is paying 33%.)

[sprucevoid]

> In practice, progressive tax curves and incentive programs let politicians meddle.

Is there cross-country comparative empirical evidence for that? My hunch is that very obscure tax curves (trapezoids and what not with layers of ad hoc edge cases) are vulnerable to meddling. But I doubt there's a general meddle-ability difference between simple forms of progressivity vs flat.