The art of balance
When people come to Taiji, the main thing they are concerned about are the hands. This is because the movements of the hands is what most people see first. The hands are important, but what is more important is the leg work.
In chinese martial arts, leg work is considered a foundation skill. Without good foundations, you are not ready to progress. You simply cannot do sword forms or lion dancing without good leg work. By leg work, I don't just mean stances, but also the way we move from one position to another. The legs should be strong, stable and not springy like Tigger's tail in Winnie the Pooh. With that in mind, your head should not be bobbing up and down. Furthermore, there are various kicks in any given style. You need to be grounded, smooth and steady when transitioning from one move to the next. This should developed when you are learning and perfecting you hand forms. Like all things in Chinese martial arts, to do anything well, it takes time and patience. No amount of classes can give you that. If the basics aren't right in hand forms, then they certainly wouldn't be in weapon forms.
What you gain in martial arts, you can apply in other activities, such as hiking, where balance and sure footing is helpful.