The barrier to mission development is pretty high, but here's something I'm hoping will lower it just a bit. I've created an in-game scenario editor, available in both Colony Game and 6-player Last One Standing flavors. You start with an empty tutorial.map, but using chat commands you can change the current terrain file, spawn units, structures, and mining beacons, change disaster settings, or even disable the editor and start a standard LOS game. There is, of course, a command to generate C++ code that can be copied into a level's source code to recreate the current unit setup. But this isn't just a tool for the technically-inclined among us. You can also generate a command list that the editor can read in again later to recreate the unit setup in-game, that even works in multiplayer!
I've attached the colony game and multiplayer versions of the map, as well as a sample script file. Load the Editor in multiplayer and have the host enter these commands to give it a try!
/changemap mp3_02.map/load sample1v1.txt
/startLOS
And here's a full command list, along with a list of (required) and [optional] arguments:
Command list (all commands and arguments are case-sensitive):
/save
8/18/2021 update: /cpp now generates calls new-style TethysAPI calls. Use /cpp_legacy for old-style Outpost2DLL calls. /python command now works but it's largely untested. Also added the /wreck and /setTechLevel commands. Fixed a few bugs.