After giving a try on different lifespans I found out that the best way to play for me it is using Normal Lifespan and, whenever I want more days within the age, also using the Potion of Youth. Usually I only stop using potions when my Sims complete an aspiration (I like them to die at the end of their lives with something like 5-7 traits).
Seasons usually takes 14 days because it isn't so long as 28 neither so short as 7 days.
Edit: it takes a while until you snowball sufficient (considering you're playing rotational) to see Sims around town doing all sort of unexpected things based on acquired skills, traits and items.