Consider we want to build a long term LEO station which serves as an intermediate stop for flights to the Moon and back (possibly with aerobrake). Refueling, docking, crew transfers etc. Several flights a year, for a couple of decades.
What would be the optimal orbital inclination for such a station? Given the Moon's inclination is non constant. And assuming we can select any place on Earth for a lunch site.
Optimal in mean launch costs. So that we could use smaller rockets, fewer launches and spend less fuel.