Although I chose leave them to free will it's really a combo with 3 others - live-in help, let them pursue their interests and keep them happy. But it's been a long time since I've played an elder, not because I play on a long life span or no aging, I play on normal, but because my games don't seem to last very long any more. I have so many situations I want to try that my attention gets fixed on some other game idea that I flit off to that. Also there are so many breaks in my Sims 3 game playing - RL intervenes or I get a new computer or I go on a building spree, etc. When I come back to playing Sims 3 I'm usually anticipating trying a new town or EP that I haven't explored yet.
My answer is based on my longest played game ( a legacy challenge that only lasted 5 generations) and the fourth generation heiress Kate Lancaster and her husband Marty (Keaton) Lancaster, who had been a vampire but took the cure right before becoming an elder. It's a good thing my general practice is to have a bedroom downstairs for the elders because those 2 spent so much time in it. I might direct Marty to go jump on the trampoline outside, which he loved to do, and I might leave Kate cooking but next thing I notice is Marty interrupting Kate, flirting and then I hear the woohoo chimes. I gave up directing them to do stuff and left them on their on. They pretty much constantly flirted with each other and ended up woohooing 2 or 3 times every day.
ETA: Recently I have downloaded some retirement homes and want to try out moving my elders to one of those sometime.