The galaxy simulation affects all players, regardless of game mode they play. If you don't want to interact with anybody, you can play in solo mode, and if you want to interact with just a group of friends you can play in a private group.
You cannot join a power and then have no competition... the other player's efforts will still affect yours.
Smuggling takes a bit of effort as well as some luck.
First you need to understand how detection works, your ship's heat signature is above your fuel gauge. The bigger it is, the farther you will be detected from. Turning on Silent Running will cap this detection range at 500M, but it will heat up your ship very quickly, so use it sparingly or pack heatsinks
You always need docking permission and landing is as you would normally. You should make sure that the system you are heading to has a black market, though. (the commodity market won't buy illegal goods)
There are no modules/internals that will hide your cargo, but you can go for ships that have a low default heat signature like the Cobra, and turn off unnecessary modules to lower your heat output.
Try going for outposts instead of starports, as they generally have much less enforcement hovering around. If you do find yourself at a starport, lining yourself up with the mailslot while out of range or flying very close to the starport will hide you much better than just moseying on in.
If you are getting scanned, don't panic. It takes a short while for the scan to complete and once you enter the mailslot, the scan is broken. Just pick up the pace a bit and get in there.
Best Answer
If you navigate to Navigation > Galactic Powers > Rating, you'll notice your Pledge Rating tab and Available Ratings tab.
Your Pledge Rating tab displays the Rating you have with the Power your allied with. Your Available Ratings tab displays what benefit each Rating supplies you with.
You increase your Rating by meeting the Merit requirements for each one.
In accordance with your Rating you'll see how many power commodities each Rating is allowed access to. For example, Rating 1 with the Edmund Mahon allows for 10 power commodities, Rating 2 allows for 15, Rating 3 for 20, Rating 4 for 25, and Rating 5 for 50.