Not all of it is super overpowered, most TO skill use or things like the ranger who can shoot in 10 mile range increments (but cant spot people at that range) are not what I would call overpowered.
Spot rules are pretty dumb sometimes. I haven't done the math, but I'm willing to bet the -1 per 10 feet rule makes the sun effectively invisible, even with however much of that is negated by its size categories.
I'm bored and curious tonight-
The distance between the earth and sun is 92,960,000 miles= 490,828,800,000 feet= -49,082,880,000 to spot check.
The Sun's diameter is 864,938 miles= 4,566,872,640 feet= 913,374,528 medium sized units. How do I convert this to a proper size modifier? I thought this was going to be simple math when I started and now I need access to algebra/calc I haven't used in a while...