I'll ask NBDY to work on the taxation system (he made the initial changes), as @Levi208 has correctly pointed out, a player shouldn't make significantly less money after reaching the next bracket and government employees shouldn't be discouraged to work legal jobs, because of the tax. There's also a problem with the base income, it's also cut and the remainder is taxed, but the base income was supposed to be part of the job salary, so it should have never been cut.
In addition, Dwayne Smith has proposed a change to the tax system, so the tax is calculated based on your income, not total wealth. In other words, if you try to make significantly more money in a short period, you'll get taxed more, but if you're rich and your income is little, you will get taxed little.