A Love So Beautiful- This will have you conflicted 'cause the SML is such a sweet guy, there were moments I rooted for him.
Autumn's Concerto- The SL is actually more lovable than the ML, but the ML goes through a lot and you can understand why he acts the way he does.
Who Are You? (2013)- FL and ML are cops and SL is her ex bf who happens to be dead. Yes you will root for a ghost and it might break you'll heart a little
Bromance- SML is a veterinary and is so sweet but FL's chemistry with ML is fire.
Emergency Couple- The main leads are divorced and the SML is their superior at the hospital they work at.
Flower Boy Next Door- I never rooted for the SL but he is a sweet guy and his interactions with the ML are hilarious.
Hwarang- How can a girl choose between Park Seo Joon and Park Hyun Sik?
Lucky Romance- Both MLs are successful and hot,very difficult decision. BUT SML is nothing more than her dongsaeng in her eyes.
Pinocchio- I really liked the SL here, I think this is one of the first times I felt conflicted about who I wanted the FL to end up with.
Radio Romance- The two MLs are hilarious and very petty when they compete for her love.
She Was Pretty- This is the ultimate second lead syndrome inducer.
1+ Sound of the Desert- Both leads deserve her and it's hard to pick one since she loves them both.
1+ Sungkyunkwan Scandal- This is one of the hardest SLS I've suffered because I love both Yoochun and Yoo Ah In.
That Man Oh Soo- Just finished this one, both MLs are sweet, hot, tall as heck, hot... Hot.
The Master's Sun- Picking between Seo In Guk and So Ji Sub will give you heartburn.
While You Were Sleeping- This one is sweet because the 3 of them are such good friends and they don't let the romantic feelings destroy the friendship.
You might have watched some of these but I got lazy checking your lists xD