...that would depend on the custom space station\'s intented use and purpose.
If you mean for a general station.. well everything, really.
If you want an automated defense platform just to claim a sector for a faction (only 1 SpcStt per sector), go for as much shield/thickness you can, and cover that with turrets. The more the better. Perhaps a dock or two.
If on the other hand you want a more active station, where players store stuff, park ships, interact, etc; You\'ll want more docks and more room on your station. Defenses are also important, though if you plan your station to be a gathering point, keep room for the ships there and perhaps assume you can delegate some of the defense to them.
If you want a mining rig, say, above a planet, well I dunno. Have either a large harvester-turret or many smaller ones. I really don\'t know why you\'d do that other than terraforming and later on turning that station into an orbital-platform, I \'unno.
There\'s really near endless shapes and sizes your station can take, and as many purposes for them as you can think of. What they need is intimately related, so really the answer is \"Depends.\"
As for the \"general basics\" (which really, is pretty much everything.), can\'t believe you forgot lights and a main room. There\'d be no point of a station without at least one room to just chill in, otherwise you might as well just make a huge parking lot.
Well, that\'s my take on the question. o:
PS: Stations are great. I love stations.