So recently I've had some Empress Ki nostalgia and it got me hungering for more Empress Ki like characters. I'm tired of the typical kind naïve easily lovable and sometimes infuriating female lead that appear in dramas. I know some people find the complex and scheming female lead hate worthy but I love a not so understandable and complicated character. A few dramas I've come across that has the type of lead i'm looking for include:

Empress Ki

Miss Ripley

Cinderella's Sister

Doctor X (she just falls under the general awesome character category)

Hwang Jin Yi

and sadly that's all I've seen that include a character who is so awesome you want to print their face on a flag and wave it around....maybe not so much Miss Ripley since she was sort of a villain but I loved the depth and realism of her character. Any suggestions fellow drama lovers?

Historical drama focusing on inner court generally feature this type of characters who kind of start naive/nice etc

Empress of China
Legend of Zhen Huan
Cruel Palace War of Flowers
King 2 Hearts
Make A Woman Cry
Romance in the Rain
Sound of the Desert
Raeng Ngao
Damo
Jang Ok Jung (didn't watch it, because I dislike Kim Tae Hee, but the character Jang Ok Jung is a really interesting woman)
Ja Myung Go (not scheming, but strong willed)
Queen Seon Duk

Hmmm... all of them are historical dramas... maybe int that era the women weren't so whiny and "cute"...
thanks for the amazing recs guys! I'm noticing that the female leads in historical dramas tend to be more awesome as well. maybe its the epic music that's in every historical drama ever. I'm starting to believe that there is no such thing as a crappy historical drama soundtrack.
You already watched one of my favorite Secret Garden she was awesome. One you haven't seen Queen Seon Duk
I totally agree. I am so tired of the meek, supposedly ugly but not really and often naive to the point of plain stupid type of female lead who is happy to be pushed and pulled about. Whilst the following dramas may not necessarily have scheming female leads they are most certainly stronger than your average female in my opinion and have some light and shade; namely Bad Guy, Ooku, Marriage not Dating, I need Romance 1, Reply 1997, Witch's Romance, Arang and the Magistrate, Producers, Discovery of Romance, Yae no Sakura, Painter of the Wind, What's up Fox?, I do I do, Secret Love Affair , It;s Okay that's Love and Jumong. The best schemer of all however as mentioned above, in my view, has to be Mishil in Queen Seon Deok with Jang Ok Jung in Dong Yi coming a close second.
Definitely Queen Seondeok - the rare drama that has both a strong female protagonist and a strong female antagonist. Also, Secret Love Affair has a smart, sexy, morally complicated female protagonist. I'd also add Capital Scandal (both the first and second female leads are kick-ass in their own ways), and if you like epic historicals, Jumong doesn't have a female protagonist, but it does have a great female lead who is definitely not the typical sweet love interest.
me too i have been trying to find a drama where the main female uses or gets revenge on the male lead instead of the other way around...they are very few the only ones iv noticed are the secondary female leads in dramas as they scheme to get the male  lead back...
While both dramas focus more on the male characters both Punch and My Beautiful Bride have several strong women.

Also:
Cheer Up!
The Myth
Nirvana in Fire (a whole lot of them, with Consort Jing being my most favourite one. )
Dae Mul 
God's Gift - 14 Days
Mother
The Queen's Classroom
The Queen of Office. Miss Kim is the baddest ass female character I've come across, she has her shit together and can excel at any task except driving cars gently (she was a bus driver) and going to after-work socials. And yet they manage to show her side as human.
If you are looking for an awesome female lead, I strongly recommend Strawberry Night -- though if you do watch this, start with the 2010 Special before jumping into the 2012 drama (there's also a second SP & feature film that follow the drama, but I did not watch those because I prefer how the drama leaves the characters).