It's scary. I've seen the damage that one person's narrow scope of knowledge can inflict on another person. I do some independent computer consultation work, and I went to solve a Houston arts group's problems. They needed help with a powerful and complex program that tracked students that they placed in different orchestras and other information. They hadn't been able to find help, though, because no other consultant that they contacted was willing to learn the program in order to support them. It gets worse: they all recommended that the arts group hire them to redesign the system using the easy program that they already knew. The real problem: the arts group was already using the correct program for what they needed, and converting to the recommended solution would have been catastrophic. These consultants were offering solutions before they even knew the problem. To paraphrase Abraham Maslov: if the only tool you have is a hammer, you tend to see every problem as a nail.
Are we a one-tool Toastmaster? I've seen people who win Humorous speech contests and then never attempt a serious speech. There are members who attend meetings and give speeches but won't run for an office, because they don't want to accept the responsibility. I've known engineers who avoid the Entertainment advanced manual, swearing to me that they can't be funny. And I know Toastmasters who won't come to a meeting that features a Success/Leadership module, because it's not the normal meeting. It's not that these people are scared to try something new; no, they've built a comfortable niche that they don't want to leave.
It's up to each of us to constantly encourage our fellow members to stretch into a new field. That humorous speaker will find that the same technical skills will make a powerful motivational speech. The established speaker learns how to delegate, set goals, and develop organization as an officer. Also, advice that I've often given to "non-humorous" speakers is to take your favorite humorist's essays or short-stories (Erma Bombeck, Art Buchwald, Woody Allen, and Garrison Keillor are wonderful) and present them in a reading. As you encourage those around you to grow, however, don't neglect your own toolkit. Try something new! Be an officer, present a Success/Leadership module, start a new club, coordinate an Area contest, or enter the Interpretive Reading contest this spring (that most of the Divisions will offer). So add to your repertoire and keep pushing until your proficiencies match that of your other skills. If you don't start perfectly, then don't be dismayed; remember the old moral: "if at first you don't succeed, you're running about average."