Actually they are not in complete chaos. There are rules for most of the subatomic particles that we know of. As isolated particles there are some very definite properties of these particles. The attraction between protons and electrons, and the repulsion of like charges(excluding neutral of course). Although every few years we find out that what we thought we knew was not true. Like for instance shrodinger's equation changed the way we think about the electron, or at least where it is located in the atom.
There is still in my opinion a fair amount of chaos in the universe though. Although it can be argued that chaos is simply phenomena caused by variables that are not understood.
And if we were able to understand completely the properties of every subatomic particle, and how it reacts with all the others in addition to finding the quantity of all types of matter, then maybe we would be able to prove that chaos is a psuedo force, and that there is a reason for everything in the universe.
Unfortunately it seems that we do not sufficiently understand matter, and energy, and with current measuring methods it seems that even if the universe is finite we will never be able to measure all mass and energy.
So for now the term chaos still holds relevance. Luck as well is a force that is and will continue to be relevant. So for now I do actually partially agree with you.