Another problem with the forced elder birthday that moves them out is that it happens too soon. Five days ago I retired one of my sims and spent all my time with another sim completing an elder event with the retired sim. I was one or two events away from completing the story (close to reaching relationship level 10) when the retired sim moved out, making the past few days useless. To improve the game, I would perhaps make moving out an option like retirement but with fewer annoying pop-ups or increasing the length of time as an elder to two or more weeks.