To me, take-offs and landings are the most important maneuvers to get good at, simply because you're close to the ground, when knowing what to do immediately is important, and needs to be automatic. Learn how to do both upwind, downwind and crosswind, practice deadstick landings, short approaches (where you come in steep and level out at the last second). Getting good at these will help you save your plane some day, when Murphy is your spotter. All the rest will come later, or you can practice the other things between the takeoff and landings practice.