revenge story in both cases but RftA has a FL that managed to be a likable one whereas in The Lady Commander I understood the anger of the FL, but could not find her methods kosher

More than one person gets reincarnated into the story filled with unrequited love, hatred and sweet romance

Love story and marriage of demon lady and a man who loves her with all his heart. Fragments of Kylin had stunning scenery and interiors. This was a much lighter (more comedy) series.

the story of lovers from two different realms: demon and human. I actually liked this better than big production with big stars

If you want a really great revenge story for a second chance life, check out Rise from the Ashes!!! It has a clever plot much better than The Double, and while a miniseries of 10-minute episodes it is done in a superb way with brilliant script, really good characters as written and acted and the heroine there is a thorough kick ass!

the story of two people with feelings for each other and just having a contract to live together. And there is a cat....

It is the story of female empowerment what these two series have in common. BiA has definitely more modern feel...

the idea of poison and transfer of it was very creatively used in Butterflied Lover. Double Life is not about the same thing but uses the main character's dilemma with the poisoned beloved...

The tone of the story is rather similar. Adults in adult relationship, life as it is and not as we fantasize about

urban story of normal people. Go Ahead was more about kids and youngsters while FITYM looks at mature life

Again, not married to someone with a hidden agenda, but successfully deceiving each other about true identity or purpose

This is not exactly the same as being married to one, but loving a female assassin while having some hidden agenda on his own...