I do Business, Legal and Ancient. I like all of them. Business is good, because it's easy and there's not much to really digest. Legal is good, because you're able to branch off the topic and discuss some really interesting things that are relevant to today's society. Ancient is good, because...it just is.
No one can tell you what subject to do, because everyone has different likes and dislikes. Just think about what you, yourself, are interested in. What other subjects are you doing?