I personally think that imputing property tax is worthwhile. Most low income people rent, not own. Property tax is paid. It should be counted.
I have tried several times to estimate effective tax rate in the US at various income levels. My feeble calculations surprised me. Once I include property tax, sales taxes, income-related taxes at state and federal levels including FICA - as best I can figure, the system is pretty close to flat.
More specifically, it's close to flat except that the tippy top does get a break. But the "flat" nature of it is that the different benefits and costs at different income levels roughly cancel out for most groups. Individuals can vary. Individuals only get full value if they learn and pursue the relevant details of the tax code.
It looked like most income levels under the top 1 in 1000 have an effective rate close to the 25% to 30% range, or a bit lower. It was pretty close to total government tax receipts and total government spending, which I used as check totals. Receipts and apparent effective tax rates were slightly lower than spending, so my attempts corresponded to the fact the govt runs at a deficit.
Examples:
$20,000 income - federal income tax $730, FICA $1530, state income tax $400, sales tax $600, property tax 25% of rent $1800, auto registration $100, total $5160 => 25.8%.
$75,000 income - FIT $6620 after deducting 15,000 in 401k contributions; FICA $5700; state income tax $3500; sales tax $1200; property tax $4000; auto registration $100. Total $21,162 => 28.2%.
$400,000 income (250k salary, 100k dividends, 50k passthrough; retirement contribution 50,000) - FIT 60,690; FICA $12,035; state income tax $18,000; sales tax $6,000; property tax $12,000; auto registration $300. Total $109,025 => 27.3%.
My tentative conclusion was: OMG, the politicians have us split between people who think our system's regressive and people who think it's progressive - when it's roughly flat already!
Obviously my MPP is that I can spend too much time indulging my taste for calculations.