Of the exposure trinity (aperture, shutter speed, ISO), aperture tends to get the most attention. The usual advice for beginners is to switch from program mode to aperture priority mode. Learn to control your exposure by manipulating aperture and thus depth of field. Next comes the "I want to blur out the background." Or "I want to be able to shoot in low light." All of this feeds into GAS (gear acquisition syndrome) where one feels one needs faster lenses to improve one's photography. Don't get me wrong, there are creative and technical reasons where a faster lens is really important. And aperture priority is often a good shooting mode (certainly better than program mode).
But shutter speed is also really, really important both creatively and technically. Longer shutter speeds are more annoying because you have to use a tripod. It's more hassle. More gear to lug around. Less spontaneous. You can't really "point-and-shoot" with long exposures (unless you are going for something really abstract). Depending on the available light, you also need to use ND filters with long exposures. Yuck, do I really want to deal with all of that? But it is the only way to create some images.
I would also offer that once you bite the bullet, get the appropriate gear (which will last a lifetime and can be used with any camera/lens), and learn good technique it becomes a very, very useful tool in your toolbox. Even if you aren't routinely using a tripod or ND filters, the experience of getting familiar with them will translate positively into almost anything you shoot.
The same could be said for biting the bullet and learning about flash photography...
