I really enjoy the way Korean Action/Adventure novels are written, so this will be the focus of the list (there are some non-action novels here though). I used to read a lot of transmigration novels when I started out, so that's why there's a lot of them. Just a disclaimer, not many novels on this list have romance in them. Anyway, here are some Korean novels I found worth reading.

Edit: The list is somewhat ordered, but I wouldn't really pay much attention to it. It's hard not to be biased towards more recent reads.