Pretty disruptive to try out big changes on a whim though such as different jobs or living location, and those kinds of changes are the ones I would think are most likely to have a large effect on happiness level.
First, you are assuming the size of the change to be proprotional to the change in hapinness level - that's a questionable first assumption! Maybe it's the opposite?
Or maybe it's uncorrelated? By default, to play it safe, keep the randomness and don't preselect for a big change!
A random change would be of any size: say, randomly try a different food today?
Then go to a aerobic class instead of a boxing class (or vice versa)
Or try swaps: if you often to go vacation on the same place you enjoy, have you tried swapping it to your main residence and work remotely?
That should be less disruptive, through all change is disruptive!
