18 vs 29 - a kdrama that follows a couple on the verge of divorce, and how a series of events allow them to reaffirm their love for each other. Alone in Love - not about a married couple, but about their life and bond with each other after they divorce. A really moving and touching drama that I highly recommend. Can't Lose - a drama about a couple that "rushed" into marriage and have incompatible personalities and how they try to iron out the wrinkles in their marriage. Very realistic ... in the sense, it is easy to love someone but hard to live/deal with them and their issues. Sweet 18 - a cute and fluffy rom-com that focuses on the life afterwards of 2 individuals after an arranged marriage. Wedding - a drama that takes an in-depth look at marriage between a couple with a shaky foundation. Hope this helps :)
Mary Stayed Out All Night Goong
I could recommand Wonderful Life (k-drama) and YanPapa (j-drama).
Definitely Massan and Gegege no Nyobo (the drama)
They are about the life of a married couple, their difficulties, their happy times, the way they work together for their dreams and how they support each other.
Massan also treats the subject of international marriage.

http://mydramalist.com/945-gegege-no-nyobo
http://mydramalist.com/11097-massan

Cunning Singe Lady (K-Drama)

a romantic-comedy drama, starring by Joo Sang Wook and Lee Min Jung
If it's focus on marriage relationship then probably I'd recommend drama family My Daughter Seo Young
what mood do you want? :p
I think married life dramas have many different approaches depend on the country and the theme 

so many of it, let me write these 4

Gegege no Nyobo
Going My Home
Gochisousan
Saikou no Rikon

I don't know the ones you mentioned but the Can We Get Married? was pretty good if I remembered right, though that was like the process to get married. I remember it being very slow but I also remember liking it a lot. 
Fated to Love You is a funny story. I didn't like it towards the end and haven't finished it yet, but some of it was pretty fun. 
Also the Reply series (at least the ones I've watched) tends to focus on the married relationships as well. 
The Lover might be an interesting anti-series for you. It's about couples living together but who aren't married, so it has that level of commitment and struggle but without the actually being married aspect part. I thought it was a pretty interesting series. 

That's all the dramas I can think of, though I'm not sure if they're exactly what you're looking for. 
Full House - starts with fake marriage, but drama focuses on living together
Prime Minister and I - She marries a prime minister with kids, and start living with them
Goong - The two leads are high school schoolmates like in ISWAK, but the guy is a crown prince. They hated each other then one day they were fixed marriage and lived together in the palace.
Saikou no rikon ('The great divorce') hilarious marriage humor
Wedding
Sweet 18

Contract relationships:

Contract marriage
Full House
Happi Marriage
Wondeful Life
Goong
Mask

This one is not about marriage but is about the process of making the arrangements for the wedding and all that, the main couple are already a couple when the drama starts:

Can We Get Married?

 Doremeduck:
I've been looking for a drama about marriage, or married life. Something like It Started With A Kiss/ They Kiss Again. Does anyone know of any dramas about marriage?

Hello If you really want a drama about marriage and life after being married while providing for the family and taking care of children plus getting at ease with in-laws I think GO BACK COUPLE is the one you've been looking for.. This is all about the regret of a young couple being married early and the real struggle of married life..hahaha beautiful stories to watch for :)

 JadeDarcy:
From your drama list I would recommend: Wonderful Life. A bit like Fated to Love You. One night stand leads to marriage and a baby carriage. (sorry, couldn't help myself). Has cute, funny moments, but also heart wrenching ones.
Autumns Concerto: One of my favorite Tdramas. The story happens over a six year expand. Living together and marriage is part of it.
Sunny Happiness is good too.
Sweet 18: Marriage between an 18 yr old girl and older man. I want to finish watching this one, but haven't been able to find any good link with higher quality video and subs :(
Drunken to love you: Similar to Fated to love you.
Delightful Girl Choon Hyang.
I hope these help.

I watched Sweet 18 on ondramanice.io.  Subs and video quality was OK for me