Side slipping is fun, its great to see how fast you can come down
Its good fun going out and experimenting with what your aircraft is capable of.
Another important thing to prcatice, which probably isn't practiced enough is slow flight, for example flying a 172 straight and level at 50kts or less. My standard of flying improved dramatically when I did the CPL, before this I would have classed myself as an average pilot, who could fly, but not particularly beautifully. During my training, me and my very good instructor used to do a lot of "exploring the envelope", very slow flight, accellerated stalls, cross controlled stalls, all sorts of stuff. We used to push it, he used to tell me to "go for it, if we spin, we'll recover".
As a PPL I had picked up loads of terrible habits, like looking at the instruments too much during stalling exercises "to keep the ball centered", so a lot of my training involved covering up all of the instruments (except oil guages) and flying by "the seat of the pants". Bloody excellent, it taught me a hell of a lot, especially when flying as slow as possible, with no reference to the ASI, but just "feeling" the aircraft, or stalling while watching the wing tip.
Good fun.
EA