Yes, I greatly prefer flat taxes (as Nedland Williams suggested) or sales taxes (as you’re suggesting) to the current system which is overly-complicated and just the wrong approach. And to your point, the prebate portion of a fair tax could double as UBI, which is nice.

I think the best thing about a sales tax is taxes are straightforward and everyone can instantly calculate the impact of taxes. I know several entrepreneurs who have to hold money back and guess at what their taxes are going to be under the current system. What a waste of time and money (since the money is sitting idle until they hear from the IRS).