"Less regressive" != progressive.
I'm sorry if that minor fact has managed to elude you.
Or did you also envision some sort of mandatory purchasing scheme in your fantasy?
Something like, everyone MUST spend 20% of their annual income (non-adjusted) on taxable goods and services?
Now THAT would be a progressive sales tax.
Oh, but why don't we just cut out the requirement to purchase and just tax their income directy?