Is there an actual drama in which you genuinely don't know who is the female lead going to end up with? Something like the Japanese Love Shuffle where things are not obvious? I am kind of sick of the scenarios in which I almost always root for the second lead, but know from the start that he has no chance. Cinderella and 4 Knights started off like that, but quickly became obvious, too.

Have you seen "Last Cinderella?" I think that one might qualify. Also I liked "Suki na hito ga iru koto" 
No, I haven't seen those two. I think I'll look into them :) 
Chuno, maybe.
Love Song
Shitsuren Chocolatier
Slow Dance
Sound of the Desert
glowing she
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Maybe dream high and goho's starry night 
They don't make em nowadays, maybe the really old k/j dramas.