I guess that was my point . . . many of the things on the list can be practiced in the process of diving for fun. When I was first learning some of my skills, we did specific "skills dives", where the only point was to go down and practice. But one must be careful with that, because it gets old after a while, and can impact one's enthusiasm for diving.
Nowadays, I prefer to do most of my skills practice either during, or at one end of an otherwise "just for fun" dive. If I want to practice midwater SMB deployment, we go looking for critters and then do a direct ascent instead of swimming upslope to shore. If I want to practice S-drills, we agree ahead of time that we will either do them at the beginning, or at the end of the dive.
That said, one of my most fun dives from last fall was going out with my dear dive buddy Kirk, to practice bottle-passing drills with two bottles. We did a very small tour, and spent a half hour or so in midwater, passing back and forth full and empty stages and deco bottles. It was hilarious.