The whole point of crypto is to circumvent the system. You just described problems that exist because there is a centralized system defining them: money-laundering, which by definition is circumventing the government, tax avoidance (same), and other loop holes that are basically a way to do what you want with your money, instead of having to share or pay something to a central authority for whatever reason.

Taxes are good, but I think that the "centralized" solution for taxing, (having a separate process, that is all defined and enforced by government) is a terrible solution that has proven ineffective, unfair, and inaccurate. Public commons like taxes need to have an equivalent smart contract and once you have mass acceptance of these tokens, people will have no choice but to pay taxes with any and every transaction, and all of the pain the current centralized IRS feels crypto has, will be irrelevant.