Let me start at the end of your remarks. Most of "the known laws of physics" do not stand outside
of quantum mechanics but rather are entirely embedded in the quantum framework. The one exception is gravity, i.e. General Relativity. The general suspicion is that when (and if) a Theory of Everything is developed it will incorporate gravity within the quantum framework. Of course, we can't be sure that will work, but the string theorists and the loop quantum gravity people seem to think it will. Most of the symptoms of that quantization of gravity would be expected to show up only on scales far from those of our familiar experience.
Earlier, you allude to phenomena connected with the quantum "measurement" problem. We do not have a generally accepted account of how a particular random large-scale experience emerges from quantum states which are evolving, according to the "known laws of physics", toward states which include multiple distinct large-scale outcomes. Maybe at some large scale the known laws of physics break down, or maybe all those outcomes do occur in parallel, or maybe both. In any case, if there is some breakdown of the known laws of physics associated with the transition from the quantum realm to the familiar realm of experience, the unknown part of the laws is on the familiar side, not the quantum side.
As for "entanglement", it's not exactly a mere theory. There are numerous experiments which show violations of something called Bell's Inequalities and cannot be explained without the entanglement intrinsic to quantum mechanics.
Probably I've missed some of your question, so feel free to follow up.
(published on 11/25/11)