I don't think our current system is nearly as robust as you think. Trump's first term laid that bare.
So many laws dictating what the president can and can't do don't have any actual repercussions for breaking them written in them because it was assumed impeachment would be sufficient. Trump showed that with our current system that means if you can't guarantee you'll have 67 votes in the Senate, then those laws may as well not exist. And every week the Supreme Court shows how much "settled case law" isn't anymore, so with a corrupt high court in his league, even the laws that do have teeth may be subverted.
We absolutely need to make changes to shore up the system and plug the gaps, but we have to do so with care that we don't end up handing new, more powerful weapons to the very bad actors we're trying to protect against.