If I’m not mistaken, Andrew Johnson was acquitted. If they want to use this as a model going forward I’d say “take your best shot”.
More to the point, Johnson not only fired his Attorney General who refused to obey what he considered to be illegal directives, but Congress had specifically over-rode his veto of legislation to prevent Johnson from firing his Attorney General.
There is legal debate about whether Congress had such authority, but Congress, the Supreme Court and the Attorney General were united in their opinion of this in opposition to the President and by a super-majority. In general, the Constitution grants the President power to refuse Congress (”veto” means, “I refuse.”), but also gives Congress the power to over-ride such a determination and to impeach the President.
So, even if you believe legislative review is a power the Founders never intended to give the judiciary, and instead reserves that power to the President through his use of the veto, you still have to recognize that the Constitution reserves to Congress the right to over-ride such a veto and to remove the President.