Hi, thank you for answering in advance! I appreciate it. I only have 3 qualifications

1.) That it be a romance without to much drama and heart ache. I dont really like romances where the main couple is sad all the time or bad things keep happening. 

2.) It has a happy ending. 

3.) Not over 6 years old. 

Side note : I am really partial to K-dramas but I am open to others. 

Also the more cute moments and skin ship the better! Thank you! 
Flower Boy Ramen Shop.
@ Seoulyramen I tried to get into that drama ages ago and never could. Thanks though! 
That Fool
Ho Goo's Love
The Lover
Boku to Star no 99 Nichi
Hi My Sweetheart

Secret Garden <3 <3 <3
Also The Greatest love maybe? I just don't remember that much about that drama so I'm not entirely sure!
Bride of the Century
Smile, You - though it is longer, the couple's so adorable together.
I Hear Your Voice and It's Okay, That's Love
Love Shuffle - a refreshing romance (it's fun, I give my word!)
I would add Secret Garden (I loveee it) but it does have some angst. :P It's a rollercoaster and never boring though. Same goes for Kill Me, Heal Me.

Since you've watched most of the best romantic dramas that came out in the past 5-6 years, you're missing out on other great dramas because of the 6 yr limit IMO. Just try Coffee Prince, it's still one of the best romance dramas to date for a reason - the chemistry, acting and story.
Korean:
- Panda and Hedgehog (2012): A pretty happy and sweet drama about sweets, not much angst, pretty easy going. 
- Cunning single lady (2014): divorced marriage drama, there was a bit of angst but mostly a funny and comical drama.

Chinese:
- Love through a millennium (2015): chinese remake of queen in hyun's man
- Whirlwind girl (2015): drama about taekwondo, not really focused on the romance but it was there. more of a inspirational drama.