I'm going to be sticking to just my Federation faction & ship style for the time being.
Making custom designs is a lot of work, making the custom tech trees is a bunch of typing and kinda trial-and-error, as you keep having to go in to game and console-unlock stuff to check everything. Lots of errors with mods aren't handled or reported in the debug.err, so it can be tough to figure out what's going wrong when something doesn't work...
It's going to take a while before this kinda thing takes off I think, but it would certainly be cool if more people started working together on projects like this 
