As LT moves forward to its final state on daily basis I want to talk about some things that were not described fully - Construction/Colonizing on planets. While we have somewhat similar threads in "Commonly proposed ideas" none of it covered that topic deeply enough.
I have no idea if Josh is planning deep interaction with planets or not, but it can be quite interesting to talk and investigate anyway.
So, at first let me share some possible concepts that I see feasible:
1. Node-like planet infrastructure.
The purpose is quite simple building and management tool while it remains possible to create complex bases/cities. The idea is to start from main building with small landing pad on it (command center) and then build everything starting from here. The more functions you want to be performed by facility the more buildings it requires.
How you build:
If you have played EVE-online you probably know what I'm talking about: you start from 1 CC anywhere on the planet and then add needed building just near in a node-like system. Every building requires some amount of materials that are simply unloaded to CC and then used until building is finished. It is possible to add some requirements for different buildings like energy, work-power etc, but using many such requirements can also make it more complex and we do not need one more SIMCITY game.

There is only one building that you place on top of the surface - every new building just adds weight to that one node.
How you build: just like the 1st one, with the only exception that you do not place buildings.
Buildable installations:
Command center - hub for all other buildings, its destruction stops operation of the whole facility. All facilities can be built in a defined area around CC.
Housing complex - determines how many workers available. Not needed if there is a city under your control.
Energy station - produces energy for other buildings. Not needed if there is a city under your control.
Transport platform - allows transportation of goods to/from planet's surface using transport beam. Can be used only in close proximity to planet without landing (if ship is too big for landing pad).
Mine - harvests some amount of all available resources that depends on planet resource richness . Can select what materials to harvest. Have different sizes.
Storage - provides storage for raw materials and built components (or storage space can be infinity for simplicity)
Weapon production facility - can produce weapons . Needs blueprint and recourses at CC.
Hull production facility - produces small ships (fighters and corvettes). Needs blueprint and recourses at CC.
Research Complex - self-explaining.
Space port - landing platform for large ships. for fast
Sensors - provide long-range detection.
Cool idea is the requirement to build orbital dry-dock (for capital ships) on colony with appropriate resources. (deep-space dry docks will be harder to maintain and they are more expensive)
Planetary defenses
It would be cool to build some BIG GUNS on surface or missile silos to defend your assets. This system can lead to interesting prolonged sieges of well defended planets. Maybe it would look like surface guns from Imperium Galcatica 2:
http://www.youtube.com/watch?v=bKkhCDhe ... page#t=951
It also possible for them to simply use capital size weaponry that is procedurally generated.
Any building can be destroyed by orbital bombardment, that makes possible for partial destruction of the facility/city. It's possible to use just raw hitpoint system with average resistance for buildings except some specialized bunkers etc. In All-in-one-node infrastructure damage is allocated randomly to buildings.

- basically "All-in-one-node" that perform many tasks at once. Can be built only using heavy "colonizer" ships that land on planet and are deconstructed to provide people with housing. Building such a beast is VERY HARD and requires some help from big factions to actually find people for new city.
Every city performs role of CC with build-in space port, infinity work-power and energy but also serves as a "sink hole" for commodities.
All of the above can help to determine procedurally generated landscape of the planet and planets "city" texture (big city - covers most of the globe with lights, preeeetyyy)
Cities can also serve as the source of credits for economy in exchange to commodities
Sensors/signature
All planetary facilities must be detected before you can interact with them (or just buy a map), it will look lame to me if I will know all colonies/bases in the system after entering it.
Every building has some kind of emission, sum of all emissions creates "signature" parameter of the base/city. If you want to build stealthy base you have to think about its size or use special stealthy-buildings. Cities have very large emission and quite hard to hide. Planet-based sensors are also big source of emission but they have pretty good radar range.
All building can be seen only after scanning while orbiting planet. After scanning you can see building icons on planet surface and try to bombard them.
I do really feel that I forgot many things to say
