I have probably seen a lot of them, but any series where either brothers/sisters reunite or sisters reunite.  I don't mind if they have a hateful relationship at points in the series as long as by the end they are fine.  

Also any series that involve a single parent finding romance, with the child actually involved in the story.  

Hopefully, there will be some that I haven't seen, and I don't care about episode length.

Siblings reunion: I Remember You (great drama, I highly recommend it)
Giant
Brilliant Legacy
Can You Hear My Heart
Unexpected You
Golden Rainbow
I Have a Lover
High School King of Savvy
I'm Sorry, I Love You
That Winter, The Wind Blows
King of Baking, Kim Tak Goo
King's Daughter, Soo Baek Hyang
My Heart Twinkle Twinkle
Shopping King Louis
Bunshin is a siblings-reunited story with a bit of a twist

First brother's story in Ojakgyo Brothers fits with single parent finding love, and the kid is a big part of the story (of that brother's story, that is)
Ho Goo's Love eventually is a single parent love story too.  And the baby is super-important in their relationship.
But you've seen both of those :)

Happy Together --- older brother re-unites w/ younger siblings 

Yea, I have seen most of these, though I have been hesitating on My Heart Twinkle Twinkle.......might have to check it out.  For some reason I have never liked the male lead.  Unexpected You is something I am about to watch as well.  
My bad, I did check your completed list and I'm pretty certain I didn't see I Remember You but Marriage Contract was on there. Oh well :P
Atashinchi no Danshi
Soredemo, Ikite Yuku
Giant.
Best siblings reuniting drama.
fated to love you......the second lead reunite with his sister.