> Make it revenue neutral and give every citizen a flat portion of the total collected revenue. Bam, it is now progressive,

Unfortunately, poor people don't have the cash on hand to hold them over until they get their Carbon Stipend on April 15th.

It's going to hurt poor people to charge them more at the counter, even if you give them more later. The stipend is just going to end up paying for less than the interest the tax created on a credit card.