Here’s what I’m going for: 
This is pretty close to what I want except for that moon surface. The problem is to get the scale right which I clearly didn’t. I’m going for the more up in between close and far away look, but any image textures are extreme up close or satellite like. I’m using a displace modifier with a arial texture, and for the material, the same image for color with UV mapping. Any suggestions for more realistic surface?
You may want to significantly raise the power of large craters (large-scale inverted Voronoi with a color ramp for a lip/rim) relative to surface details. Your reference image has lots of large-scale displacement, and very subtle small-scale displacement.
the second version is obviously going in the right direction, I’d lower more the displace on that texture.
The issue you’re having is that you try to solve everything with one texture where you should think in term of low medium and high frequency noise, or different scale of displace/bump.
What you’ve got is a good high/mid frequency level, that makes some kind of rocks.
Try to add a tweaked sand texture, as bump and color to make the high frequency, small bumps.
And add a broader texture , to get some “mountain” as a big displace.
You can take a small part of this texture :
http://blog.apoapsys.com/2013/05/23/bored-then-create-a-planet/
Here’s take 3. I’m pretty happy, but the detail up close I feel could be better. I don’t know but it still feels like something’s missing.
As far as earth, any suggestions on how to make it brighter? (without illuminating the bottom)
I don’t see any problem with the current brightness. Although the answer is, with the current lighting setup / colors you can’t. You have to upp the exposure and reduce the brightness of the moon surface diffuse-color.
You can also play with unfocusing / glare / reduced color if you’re after the limited quality photorealism, but I like the crispness of the render as it is now. My only nitpick right now is that I think the clouds on earth have a too strong normal mapping. And perhaps the moon surface looks a bit low res compared to earth.
Good job tho for sure.