Is the Sixteenth Amendment a "good" amendment?

No. In fact, an income tax that is progressive (in which the tax rate adjusts for income) is in violation of the equal protection clause of the Fourteenth Amendment, assuming that amendment's viability. It is illogical that they can both be simultaneously enforced. Whereas there is a legitimate argument to be made in favor of a government right to tax goods, it is a dubious position that the government has the right to tax income.