A Modest Proposal for Taxes (with a question)

I was thinking about an economist's pipe-dream tax regime.  The core elements are a flat rate income tax, with high standard deduction along with a wealth tax. A standard tax credit and child tax credit would also be included. There's redistribution with a minimal impact on work incentives.

My big question:  What rate for the flat tax rate would be required? Let's talk specifics.

The standard tax credit and child tax credit would replace the EITC*. To keep it simple, set the tax credit to $4000, the standard deduction is $25,000, and keep the per child credit at $2000 per year. Everyone now eligible for for the EITC would get more; for those with no children, much more.

The wealth tax is 2% on wealth over $20 million. That rate is low enough so that passive investment returns would cover it. (Another thought: has anyone ever suggested indexing the wealth tax rate to a long term bond yield? Higher yields mean higher passive returns and tax revenue, right when the government needs it.)

The standard deduction and tax credit are equivalent to a negative income tax, the simplest way to accomplish income redistribution in way that doesn't affect work incentives. The wealth tax has similar advantages without seriously affecting investment incentives.

So, given all this, what (flat) income tax rate is required for revenue neutrality? Public finance experts, please help......

*Earned Income Tax Credit