Simple movements will expose you. Therefore, they should be, and are, all you need to evolve in your body-knowledge. Developing an understanding of what skilled movement patterns require takes patience and commitment.
I thoroughly enjoy this process! Lowering repetitions, yet keeping time under tension high has forced me to engage more, mentally.
In my profession, the plank allows me to assess where the client is weak. Their limiter could be core-strength, unactivated glutes, poor leg-tension, weak chest, weak shoulders, weak triceps, or an un-present mind. Movements are linked and connected, thus, how you do one thing is how you do everything.
Modifications are numerous. The plank can be performed from your knees, or with hands on an elevated bench, chair, or bar. Yoga blocks and parallettes are fun additions.
Simple Implementation. 1:00 Plank. 1:00 Squats. 1:00 Walking Lunges. 1:00 Rest. Repeat three times.
Free your mind and make it happen.