In this game, eventually players will have houses. Now, what would be nicer than allowing the players to build their own houses? In order to allow any player to build his own house without forcing them to learn some serious 3D modelling skills, a construction set will be needed.
One of the best construction sets I know of is the morrowind construction set. It allows you to build any structure using pre-made building blocks that fit together seamlessly into a 3D structure. For instance, a floor, a wall, a cooridor, etc - The game has a large number of different styles and a complete set of blocks for each style, allowing you to build basically anything.
OF course, planeshift is an MMORPG, and while in morrowind cheating by making mods hurts nobody, in planeshift some careful measures aught to be taken to make sure the system is foolproof. A number of things have to be taken into account.
First, any player will only be assigned a certain amount of land that can be edited, land which must be bought IC. The construction itself will be done OOC, but might take time and money IC too. Also, the exterior building style will be determined by the location of the land bought, and certain problems, such as the maximum size of the exterior structure, may have to be addressed. All buildings should fit the general style and feel of the area they are built in.
Interior areas should not be limited by any regulations. Just allow people to build what they like - It\'s their area and they should be able to build it the way they like it. However, only static objects and furniture should be created in the editor. No NPCs, objects that can be picked up and sold, etc...
This would give players enormous freedom to build themselves a nice place in planeshift, without unbalancing the game too much. It would also allow players to help the devs in creating new towns etc without having to be experienced in 3D modelling. There is one problem however: All mods created by any player have to be transferred to all players. There is a way to do this: A good version management program. The good part is that a mod file can be extremely small: It can consist of a list of references to objects. For the references, a few fields would suffice: Position, rotation, size. Even for a large mod with hundreds of objects, such a file would not exceed a few kb. This can easily be downloaded on a need-to-know basis, i.e. when the player comes near to or enters a structure.
I think such a construction set would be a great opportunity for planeshift to become truly unique, unlike any MMORPG.