Are Italeri 1/32 figures even worth it for practice?

Sure they would be. They may not have the facial detail to get the practice you want there, but they will have clothing to work on the folds, highlights, and shading, among other things. If you want something better for a similar price try the Airfix Multi Pose sets in 1/32. Six soldiers for less than $10 at most hobby shops. Only WWII stuff though. Or you can look for the older Airfix single figure packs. American Revolution, Napoleanic Wars, English Civil War, French Foreign Legion, several mounted figures...