If you wish to broaden your academic horizon, I recommend that you study business management. Especially, if you are planning on starting a company, be sure to be familiar with accounting, economics, and business management. You could either take classes at KAIST or read books regarding the topics.
These are the basic knowledge one needs in order to easily understand how a company works, and how you should behave. Further, I suggest that you keep a close eye on international affairs.