I don't give tens or nines easily. ATM I have one drama rated a 10 (a kdrama) and one drama a 9 (Juhan Shuttai, which you have on hold). if you don't mind me suggesting some of my strong eights, however:
My only 10 is a Japanese movie, Love Exposure. Among my 9 (I have only 10 among 111 movies/dramas), I could recommend Dear Sister and Rich Man Poor Woman for romance and Kurosagi or Ouroboros for suspense/action.
From 2017: I gave a ten to "Byplayers", but I'm afraid there are no English subs. I gave a nine to "Izakaya Fuji" but again, I don't know about English subs for this show. Finally, I gave a ten to "Quartet" and I'm pretty sure you could find English subs for this.
I second the recommendation for Last Cinderella! It was such a fun drama to watch :) If you're up for something with a serious tone and a lot of tearjerking moments check out Soredemo ikite yuku. It's definitely a 9/10 for me and I'm so stingy when I rate things haha