>I don't think time will be any more difficult to understand that the workings of our solar system, once someone gets around to defining it.

Time: the abstract analysis that something has changed state, there is a before and an after.

Millenia ago some Greek dude named Heraclitus discovered the idea of "change," he said you cannot step in the same river twice. This idea of change is interesting, but it might have interjected alot of problems as everyone seemed to assume that change happened in time. The idea of time already existed, then change was discovered, it seems like a natural conclusion.

No one has really suggested that change is what causes time. It makes as much sense. Even more if you consider the fact that change is also what creates space and matter. What I mean is this, science seems to think:

Matter exists and interacts in the medium of space and time.

I'm suggesting:

Change occurs and matter, space, and time exist as a result.

This is a finer interpretation if reductionism and Occam's Razor are prefered.

>I think the speed of light is absolute and constant in the vacuum of space.

This is true on the scales that we are most familiar with, but there are amplitudes of photons that cause light to travel slower or faster than c. Its simply that these amplitudes cancel out over most distances. The only time the variable speed of light is important is when you're discussing quantum electrodynamics and very very small phenomena. I suggest Feynman's QED if you're interested.