Need some J-Drams recommendations

Romance: Last Cinderella, Hotaru no Hikari, Rich Man Poor Woman, Hana Yori Dango and, if you're in the mood to cry your eyeballs out, 1 litre of tears.

Detective: Kagi no Kakatta Heya, BORDER (just came out last season and I really enjoyed it :3 ), Kurokouchi (I really liked it, it was a different approach to a detective drama, it was very interesting), Hard Nut! (this one was maybe a little bit sillier, but I just loved it way more than I expected to :D ), Ataru.
There's also, Boss, Galileo, Dr Brain which are very popular amongst J detective dramas but aren't some of my personal faves.

I started my drama addiction because jdramas, so they will always have a special place in my heart. Here is my list in no particular order.

1. Zettai Kareshi - it was one of my first dramas. Not the best out there, in my opinion, but it's really worth a try. Many people have it in their favorites
2. Hana Yori Dango - you simply can't say you watch jdramas without having seen this. If you heard/watched Boys Over Flowers, well this is the original version and better. The chemistry is touchable and the main couple is one of the most loved in dramaland (the inventor of "second lead syndrome")
3. Nobuta Wo Produce - if there is a thing that Japan is good at, then that is "slice of life". This is a heartwarming story of three friends, you won't be disappointed
4. Yamato Nadeshiko Shichi Henge - my first asian drama. Loved every minute of it. It has romance/mystery and weirdness  
5. BOSS - great detective drama. It has humor and interesting characters. You won't get bored
6. LIAR GAME - if there is a must-watch then that is Liar Game. It's interesting, captivating and it has Matsuda Shota(you will know what I mean if you watch it)
7. Itazura na Kiss - Love in Tokyo - this is more recent one. If you watched Playful Kiss or It Started With a Kiss, well this is another remake. That doesn't mean it's not good, I really liked it
8. Kimi wa Petto - if you like the popular "noona-romance" type of drama, then you should give this a try
9. Tatta Hitotsu no Koi - one of my all time favorite in dramaland, this is simply the most heartwarming story out there
10. Love Shuffle - really interesting, it's a combination of romance with psychology
11. Lucky Seven - another detective drama. the humor here is great but also the storyline
12. Gokusen - this is neither romantic nor detective drama, but I simply think you should give it a try. I assure you that most of the jdramas lovers on MDL will only speak greatly of it

I agree with Hana Yori Dango and Liar Game.  

Nodame Cantabile, Gokusen and Tatta Hitotsu no Koi are also classics worth watching :) 

Romance: "Pride" and "Buzzer Beat" must in list^_^

Here's a couple of more J-dramas for you :)

Orange Days - Romance 

Hanzawa Naoki - Business drama (give this a try if you want to watch something compelling)