From my understanding player-constructed stations are completely immune to GoD. Only stations that exist at the start of the game are affected (apart from tractor beam factories I believe, which are a special case because they kept disappearing in previous patches before anyone could buy tractor beams).
Of those factories that it manages, as long as they're shipping product or buying other products or have a player ship docked they won't be removed. There are also rules about re-adding stations but I don't know what they are. In my current game the Solar Power Plant in Jupiter has about a 50/50 chance of being there or not.
As for drugs, they sell extremely well, especially Space Fuel. I have a complex in the unknown sector in TC that becomes known as Avarice using every asteroid and it sells Space Fuel as quickly as it can make it. You can even abuse it being illegal by making a complex in regulated space and freight scanning every ship that leaves.
I've never tried to make Squash Mines so I can't comment on them.