In my opinion for death to stay impactful, it should be rare. The more the sims drop like flies, the more it loses its dread. That's why I think you're doing the right thing with aging down your elders.
(In my game side saves are fair game, the sims dropped like flies in the Oregon and Moby D. challenge, but in everything connected to the main timeline I curate sims dying havily. Since I play so many side saves, my main moves very slowly, and is set to aging off anyway, therefore I rarely run into that problem.)