I'm not going to pick any of these answers because none of them really approach my viewpoint here.
I'm also not going to push my philosophical beliefs on others. The only thing I'm going to say is that the first option, 'God is Darkness,' is the only one I believe to not be possible, from a scientific perspective.
We have a number of terms that are not phenomenon or forces in and of themselves, but rather describe low quantities or absence of other phenomenon. 'Darkness' falls into this catergory.
One example of this is heat and cold. There is no such force or energy type as 'cold.' We use the term 'cold' to describe low amounts of heat. Heat itself is observed as the amount of activity within a given mass at the molecular level, ie. How quickly the individual molecules are moving around. Absolute zero, as cold as it can get, describes the condition where all of that movement ceases.
Similarly, 'darkness' is not a force or type of energy, but rather refers to absence of visible spectrum light. Light itself is composed of photons, which are particles that blur the line between matter and energy somewhat.
Terms like 'dark matter' and 'dark energy' do not describes forces of darkness as their name would imply- rather, it is a reference to darkness being an absence of visible light. Dark matter and Dark energy refer to theorized matter and energy that is, with current technology, not detectable, similar to how you can't see whats in a darkened room. It is believed to exist only because of the effects we can see it have on visible objects.
So no, you can't really describe God as being made of darkness because darkness itself isn't a force, particle, or any kind of tangible measurable thing, it is nothing more than a word used to describe the absence of light.
As for the main question- "If there was darkness before light, why is God more associated with the light?" I'll answer you this- in any profession where something is created, that profession tends to be named referring to the end product, not the initial condition. A clockmaker isn't associated with a pile of metal, but rather the finished product. As those of the judeochristian faith attribute the creation of light itself to God, it would make sense to associate God with light, the product, rather than "darkness," the initial condition that (as stated before) isn't actually any kind of material or energy anyway.