I have aging turned off (I do it manually) and I really wish households functioned like they did in TS2 (or had an option to set it that way), where each house had time "stop" when you weren't there. So their needs were full, ready for work and you rotated, you wouldn't come back and find them starving, cold, and late to work with their tasks not completed (even though they were when you last left the lot) because you played some other households for a while. I HATE that gardening only grows at 5 AM on that lot. Play 23 hours on one lot and have your sims go somewhere? You've missed that day's harvest.
And finally with seasons, only the house that you are in when the event/holiday ends is the one that gets the benefit. Otherwise you have to play through the whole year or create Christmas every day of winter and rotate houses... (sigh). I'd like to leave a family in summer, go back and have them still be in summer, since I try to play around the neighborhoods to grow up the kids together.
I love seasons, but the calendar needs to be attached to each lot, not for the entire game. It's not like the loading screen of each neighborhood shows you what the weather is for that area... so having each lot have their own calendar and have it not move when that house isn't active would be AWESOME.