My Proportions mod (see Gold) addresses issues with population trasport, population growth, population effects on both production and construction (different curves) and colony development versus developed homeworlds. Of course, it does make it take years to build up colonies that can add much to the output of a homeworld, but the homeworld itself is enough to field a decent fleet. That is, I like realistically slow development, but probably a lot of players' reactions would be along the lines of "WTF! It takes forever to fully develop a planet!"
PvK