VATs and sales taxes are regressive. I'm continuously astonished that people seriously talk about replacing our income tax system with them.
A VAT alone would be far too regressive but combined with a sensible income tax (and credits) to counter-balance the regressive effects could be a big improvement over the system today. I don't think I've seen anyone propose having a VAT replace income tax.
"Ease of enforcement" is an irrational standard for designing tax systems. If you want to lay off the rich in the hopes that they'll create jobs, just say that.
was the part I was addressing. While I agree that I've re-stated it, I don't feel that I've mis-characterized it, or if I've done so, it wasn't intentional/strawman-ish/troll-ish.
While I'm not suggesting that likelihood of collection should be the prime design criterion, I would have to rank it fairly highly, both for practical reasons (the money must be collected) as well as perceived fairness reasons (it would be ideal if people felt that everyone was paying their own share, rather than seeing material underpayment of tax, or believing that it exists, either of which creates incentives for that person to also cheat)