Whats the difference (please read)?

Okay, so obviously the US revolted against Great Britain because the King was only checked by Parliament who was controlled by Lord North and the Conservatives. So they revolted for their rights. Well, today people say, "I hope the Dems/GOP get 66 seats in the Senate and 200+ in the House that way they can p whatever they want". Doesnt that sort of defeat the purpose of not having a Monarchy or Autocracy. Because say the Republicans had the Presidency, 70 seats in the senate, and 260 in the House, then they can do whatever they want with healthcare, the war, the death penalty, etc. Well, Wouldnt it be better if the Republicans had small majorities in the House and Senate and the Dems had the Presidency? That way they have to compromise and their is a balance of power so that no one gets too powerful to make any life altering changes? So my question is, do you think that having a balance of power is good, or is it better for 1 side to be in charge? And please do not say something like, "You're comparison is not at all progressive" because I can tell you that when William IV was in power, he had a Whig parliament and that forced him to grant more social reforms (labor laws) and the Whigs did not turn the UK into some business punishing socialist state because he could dissolve parliament. When either party has total control, people get pissed off and then they make choices that they later regret.