Really interesting read, and this thread actually convinced me to join the fun, as I saw what is possible in GalCiv3. Very honest dev blog, kudos.
I have only two questions regarding this also considering future implementations:
Will we be able to design shipstyles / shipstyle groups for the ai civs, to be usable without mods, to ensure fair custom civing for multiplayer?
Generally the ship designer being accessible for a race (even out of running game without cheat console), would be great; saving a "template" of ships for a race - at least visual templates - would allow vanilla custom factions to be used in mp more fluidly.
And the second is regarding the tech tree discussion, it would be nice if the wiki had a comparable view of the global tech tree, and which techs are unique in kind of an overview thing, to see which tech tree fits the race best. While mods can add their own tech trees, releasing some custom tech trees for custom races, like there are planet systems, would also be awesome.
On a personal final note, which does not need any comment...
These customization options go a long way I think, in popularity, especially since other games lack that for multiplayer; and never before have I enjoyed hour long sessions of playing round based games with strangers before in such scales, as nowadays.
Regarding DLCs i would be happy if they only give new stuff you can use and play against, but while non-owners might not be able to use it as playable race without owning said dlcs, they can still participate in the games with other civs, or play against them as AI. Nothing turns down more than DLCs which are forced to be bought just to join games, while the other way around, you always see it as an investment you personally choose to give, to be able to have more options.
In this regard also kudos to the free dlc, even if the @ bug quite makes it tricky to do so.