Elemental was a very modifiable game, extremely data driven using XML and so in theory great for modders.
However although the game was very modifiable, this modifiability was not very accessible to the average player. Information on the Schema of the various XML documents was hard to access although the community did start to build up a repository of this information after a while. I feel that this meant that largely Elemental hasn’t really lived up to it’s potential for modification.
There was also the fact that XML can be intimidating to those who are unfamiliar with it which may have put some people of, (although in fact once you get to know it XML itself is simple.
For GalCiv3 you are distributing on Steam and using Steam Workshop will make mods a lot more visible and easy to distribute and you are again making the game very data driven via XML files. So it should be a modders, but I think you need to address how you make modding the game more users friendly?
My suggestions publish the XML schema’s for all the document types you have with some explanation of how the engine will interpret them. Can I have an XSD?
Are you ok with the community building tools to enable some of the files to be edited via a user friendly UI? e.g. create and distribute their own editors of various aspects of the game? Will you be providing any Modding tools directly?
Have you considered using the part based sovereign editor used in elemental to create an Alien race editor for customising you race e.g. for diplomacy, etc. in GC3?
I know the standard races use pre-rendered video which gives a better quality but one of the things I’ve always wanted is to be able to customise my race easily in a visual sense and short of sticking to a still image the only way of doing this at the moment is to create, rig animate and render in something like blender then convert to the right video format. If you plan on using custom races from one player to fill out the race rota for other players on large games wouldn’t this system be great for adding variety.
You could start by choosing a basic form e.g.
Humanoid, Quadruped, Cephalopod, insectoid.
Then have parts you can attach and customise for texture, size, orientation relative to the attachment points.
It would be a sort of cross between the ship editor and Elementals sovereign editor and I think would be a real selling point of the game.
These models could then be used for diplomacy animations, advisors, etc.
I think this would add something special to the game, and give races as much love and uniqueness as ships.