Galileo

In regards to your first issue of your game crashing with a SOI change from kerbin to moon, I have never actually seen or experienced this issue, but I may know why.
try deleting your settings.cfg from your ksp directory. This is a little inconvenient but it will help me narrow it down. You will have to reset all of your settings again.
Also, delete the GPP_TerrainDetailPreset.cfg from the GPP/configs folder. Then try the SOI change again.

In your steam library, right click on Kerbal Space Program and go to “Properties” 
then click the “Betas” tab.
then select the version of ksp you want to install.

Stop forcing OpenGL 

Mac OS is a 64 bit only operating system. That being the case, KSP can only be run in 64bit and does so by default.

EVEs cfgs and textures are basic representations of what EVE can do.
SVE is a higher quality pack of textures than what EVE provides and has custom scatterer atmospheres for the stock bodies. It is more demanding than default EVE, though. 
Best way to see the difference is to try it yourself. 

Kinda. 
SVE uses its own textures and cfgs, but it uses the EVE plugin for its effects. 
SVE is more performance hungry than EVE because of a few reasons:
Default EVE is just a very basic example of what it's capable of and doesn't do anything special.  SVE utilizes nearly every effect the plugin is capable of including dust storms and snow. This will obviously cause a drop in performance.
SVE's textures are higher resolution. Higher resolution = Less FPS. There is a medium and low version if your rig can't handle the high res. The low version might actually run faster than default EVE but the texture resolution is only 2k resulting in pretty poor visuals, but it's better than nothing for some people. 
And lastly, SVE depends on scatterer for best results. This is really the biggest performance hog. However, turning off certain features help with performance, namely the ocean shaders. 
There really is no better way to find out what will work for you than to try it yourself. Good luck!
 
 

Yeah the 1060 will do just fine. It's overkill for ksp, but that just means you will also be able to play other more graphic intensive games as well.

The game is currently being worked on for consoles with a release in a few months. This will come with a lot of fixes, many of which you are experiencing. There are quite a few threads detailing the development of console versions. Currently, there aren't any fixes for your issues unfortunately. You, like many other console gamers are just playing the waiting game.  

At the bottom of your original post,   there is a little button that says edit. Scroll back up to the top and you will see the input box that your title is in is now editable.