Far too many people can't see beyond their tax refund and they have no understanding of what they actually pay. This current system has too many hidden taxes and compliance costs and is way too complex. I know this from my experience as a CPA and tax accountant.
If the Fair Tax (or something like it) is passed:
I pretty much agree with what you say about how legislators can and will abuse any tax scheme. In particular, the three reasons you give. i.e., continual rising rates, inaction by the electorate, and government cronyism, can corrupt any tax scheme. I just wonder why you singled out the FairTax in Post 12 since all tax schemes are subject to the same kinds of abuses.