We go through phases of enjoying one set at the expense of others. This has proved a reliable constant for the moment:
6 x 25m Fly + 10s
6 x 50m Fly/Back +15s
6 x 75m Fly/Back/Breast + 20s
6 x 100m Fly/Back/Breast/Free + 25s
This works to allow you to give emphasis to any of the strokes by shifting them all round. Thus, to ‘enjoy’ backstroke, you do the same but start with back – the 100s are Back/Breast/Fly/Free.
Another variation would to double the distance while reducing the number of repeats.