Again, from the frontier army example, one way to age the force may be to allow people to remain in certain ranks/grades longer than we have previously. This has been touched on by some of the military personnel system reformers, and I really feel it deserves a second (and third) look. Shoving majors down to company command level creates expensive companies, but allowing a captain to remain at that rank and lead his company effectively for a few more years gives us the baseline experience without clogging the ranks with more "leaders." Again, to draw from the frontier army level, majors were often used as either fort commanders or as squadron/battalion commanders (at this time in our organizational history the squadron/battalion was an ad hoc unit containing from two to four companies depending on tactical need). They served a purpose, but didn't clog the smaller units.