If you loved Song Joong Ki in DOTS, you won't regret watching him in Innocent Man. It's his best performance to date.
Similar plot of a modern girl travelling back time (maybe that's the only similarity haha). But you won't regret watching Moon Lovers (my favorite period drama, along with The Moon Embracing the Sun)
The two dramas came from the same source material, Tong Hua's novel - Bu Bu Jing Xin. If you loved Moon Lovers, you might also want to check the 2011 Chinese drama adaptation.