I highly recommend:
Team Medical Dragon (Iryu),
which is the BEST medical drama EVER.

Bloody Monday,
about terrorism and cyber world. Amazing acting especially by Narimiya Hiroki and great story!

Hotelier,
an old drama with a beautiful story. The scenes from daily routine in the hotel is pretty cool.

K.O. 3an Guo,
a spoof of Chinese "Romance of the Three Kingdoms". One of the series of K.O. One and The X-Family.
This drama teaches us about friendship and loyalty. The friendship in this drama is amazing! And it is completed with all the romance and of course, the humor. If you like "Romance of the Three Kingdoms", this drama is very recommended!

Three Kingdoms,

if KO3an Guo is a spoof, Three Kingdoms is the real history. Don't let the 95 episodes discourage you; i enjoy every bits of it! There are many scenes with deep impression. And the casts are superb!

Reply 1988,
the third installment of Reply series, I've watched all the reply series and this one is definitely the best. It deals with friendship and families. I fell in love with all the characters, not only the leads but also all the family members. This drama is the kind that makes your heart warm. 

Battle of Changsha,

well if you like Reply 88, then you def have to check this one. The bond between the family member is so sweet. And Wallace Huo is just pure <3

Incomplete Life (Misaeng),
this drama deals with working place and the reality of life. The reason that I and lots of people love this drama is because we can really relate to it. It conveys the story in such a way with no unneeded "drama", but you can really relate to it with your life somehow, even though you are not working in a Korean company. "Incomplete life, complete life.. In the end, we are all still incomplete."

In a Good Way,
a Taiwanese drama that deals with romance and friendship in college, it shows the development of the characters and yes, the story has less dramas that you can really relate to it. The romance between the main couple is very sweet. And friendship story in a Taiwan drama never disappoints.

and Princess Hours (Goong),
a funny and beautiful love story. I've watched it so many times and I still find it interesting.