Oof I can't decide!
If I was with Derpy I would buy a big bunch of muffins and go to a picnic and end up with us looking at the stars or lost in the forest.
RD, I would go in the town, eat a pizza (vegetarian please), go at a movie, paintball, video games at my place (I think RD would enjoy a shooter)and in the end looking at the stars. (really that is the best ending you can get)
Lyra? Everywhere I go! Probably taking her around to see what humans do, maybe a documentaty on us, anything related to humans!