I love exactly same type of MLs, because as u said it's more "human" and realistic, this is the reason SML s are more often realistic and likeble but then you are disappointed because you start love SML and then he looses everything to ML.
unfortunately there are few good dramas without these kind of cliches and even fewer with charismatic but not good ML. though in my list many will be without happy ending, because this kind dramas mostly are high class, great but not happy ending type, also I love when FL chooses/loves him even after knowing he is bad. it is rare but most of this dramas have it.
1. Cruel City this show is perfect, exactly that kind of ML, he is cruel, bad, also badass, cool, smart and sexy, gangster... I want to say more great things but you should watch it without spoilers, every episode is mind blowing. and romance is amazing, emotional and even sexy (there is even sex scene). it's really different drama, without "asian drama rules" you will even think it's western.
2. A Love To Kill also bad (not so bad but bad for her, she is his revenge target, but falls for her) guy doing bad things. but this is quite sad drama, Love to kill was heavy for me, half of the drama has sadness. though I was glad that watchd this amazing story and they both are soo beautiful.
3. Lucifer (devil) even with name you can say he isn't good, but police can't catch him because of his masterplan, he even doesn't do dirty job himself, doesn't kill but people are killed because of his wish... you will see
4. Flower of Evil - Great Great drama, very high class. amazing acting from both (good actors are many but really good acting from actress is rare, this show has greatest female acting I ever seen in asian dramas) deep emotions. great story, every episode is unpredictable and great. he is sociopath and maybe killer with dark past, she is detective
5. The Smile Has Left Your Eyes great drama great acting. dark maybe killer boy
6. Kill It killer and detective
7. The Innocent Man
8. A Man's Story I liked that SML is more star of the show, he is dark, emotionless and every character including his own father are trying to distroy him, but they cant, he is too smart and wins every time. only FL will be by his side. and ending scene is unforgetable
9. Hello Monster it's not romance (there is romance but bromance is more emotional) but trust me, it's must watch, real bad guys and real emotions, I watch dramas for romances, but this was better then most of the romances