Because I can.
Adds a Mobile Construction Vehicle to the game, that can deploy into a Command Center able to build and repair structures by itself. This mod replaces builders and builder ships with engineers, and changes combat engineers so that they can only repair (their cost has been reduced because of that). Experimental Spiders remain the same.
Engineers look exactly the same as the default builders, but hover, cannot be built from the command center and are only able to repair buildings. Their cost has also been reduced slightly.
The MCV overrides the starting command center, and can be built for $2500 in a T2 land factory. They are slow and unarmed, but have high HP. Once they deploy into a command center, they cannot repack. Since resource pools take longer to reach now, the credit generation rate of the command center has been doubled.
The AI works fine most of the time, but they tend to take longer to start building an army (unless the map has several resource pools near their spawn). This mod probably works better in multiplayer, but singleplayer skirmish doesn't have any serious problems.
Want the MCV, but still want builders? Check out my "With Builders" version: http://steamcommunity.com/sharedfiles/filedetails/?id=1309322606
NOTE: This mod might break some campaign or challenge missions. There's nothing I can do about it, it's a consequence of replacing builders.