Topic suggestions:
(1) Current events. Anything that is current news - Korea or worldwide - could be discussed at a suitable level introducing new vocabulary, expressions, grammar structures. For example, the recent election, the oil spill at Taean, Ssangyong's new 100 million won sedan, the death of Choi Yo Sam (from today's Joongang Daily).
(2) Discussion of daily events in a family, e.g. my step-daughter returning from visiting her grandparents in Jeju-do and complaining that they kept the heating turned off to save money, going to the bank, getting a part-time job, what to do in the vacation.
I also hope that you will be making some more intermediate lessons soon. I joined this site as a Premium member on the basis of the two intermediate lessons I found when I took my free trial and was pleased with the good quality podcasts they offered. However, I am starting to feel that I made a mistake as there is nothing to follow the 2 lessons and there doesn't appear to be any plans for new content. It's the holiday season but still ... after my initial high expectations, the daily barrage of emails ("I'm confused ... ") with reduced price offers, now I 'm waiting for some signs of life^^
Kevin