What language areas do you think you want work on to be a well qualified English teacher?

These days, more and more people are concentrating on improving their ability to speak in English. In the past, particulary in Korea, English education is mainly focused on English grammar and Reading comprehesion. I am not sure about why this situation occured, however we can say that it is different now. In fact, there are a lot of news saying that current english education is being changed to improve the actual ability to make students have a good command of comprehensive English. For example, the government tries to recruit some teachers who can deliver a lecture in only English.
So, I think i should keep pace with the times or might die out as a incompetent English teacher. If someone is to be a English teacher here and now, he should not be content with just an ability to have a talk with native speakers but can deliver a full lecture in English. I know this takes a very long time and troubles. However the different age and the different consumers of English education compel us to provide the good-quality English lecture which can make students exposed to English freely and frequently.
In brief, I want to study about speaking well, i mean, whetever it is, i want to have a full command of speaking English like native speakers.