The Sims 4 wishlist game!

[Caspin]

The ability to stroll randomly around worlds.

I imagine this would involve clicking on your sim and choosing something like "go for a walk" or "wander round town" or "amble aimlessly". Choosing this should give you a tiny increase in athletic skill (as should cycling!) and would enable sims to gain other benefits such as a "relaxing stroll" moodlet or "enjoying the fresh air".