I just recently finished Long Vacation and Tatta Hitotsu no Koi and found them both refreshingly organic compared to many of the interminable kdramas I've suffered through.  Anything in the same vein as these?  I'm open to pretty much anything as long as it's short (<16eps), but a non-Korean, older series with good music would be a plus.

Orange Days and Aishiteiru to Ittekure are also written by the same author as the two you mentioned
Arifureta Kiseki, maybe?
^Those look right up my alley.  Thanks!
Rich man, poor woman (set in working place, their chemistry is too cute, seriously watch this)
pin to kona (set in high school, really cute)
my rainy days (it's a movie, really nice atmosphere)
Please Love the Useless Me (this is romance and funny af, also this is quite new)
Proposal Daisakusen (this is older from 2007 but still good)
I have tons more but not sure if you even like the ones I recommended so far so I'll stop here lol and of course all of these are 10eps, good length without any unnecessary dragging parts.
Maybe these would be of interest?

From Five to Nine
Koi no Chikara
Brand
Star no Koi