Watching slumps usually happens for me at one or twice in a year. What I do is. I take some time off watching and do other things --read, write watch Ted talks and etc.
But for recommendation, here are mine. Though I don't know if you will like them...
Misaeng - speaks to me like no other drama did. And it is the most realistic drama for me. The narrative is just a masterpiece
Signal - one of the most brilliant dramas ever. The suspense, story, characters, acting, pace, chemistry, sync. This really is a must watch drama
Healer - adorable chemistry between the leads, suspense and thrilling story. And has so much depth
My ahjusshi - one of a few dramas that really focused on characterization.
Nine times travel - time travel dramas are usually tricky but I love how very concise and perfect the time travel rules are in this drama.
Movies: Miracle of cell no7, Berlin file, roaring currents, a taxi driver, eungyo