I haven't watched Reply 1994, but many of the dramas you mentioned I loved as well: reply 1997, I Miss You, My Girlfriend is a Gumiho, My Love From Another Star, Sungkyunkwan Scandal
I really adored Shut Up Flower Boy Band, for reasons similar to Reply 1997 and Sungkyunkwan Scandal. I adore romance and when I'm looking for a drama, that's pretty much all I check. There's a fair amount of romance in Shut Up Flower Boy Band, but like the two other dramas I mentioned, there came a point where the friendships between the characters engrossed me so much I ended up being even more invested in them than the romance (even though I liked the romance). I thought it was the kind of show one could easily relate to, because it depicts adolescence in a way I felt was quite accurate: intense, so cool yet so awkward, bittersweet, finding you place, facing a reality that compromises your dreams, growing up into your own self without letting go of your friends... The drama made me feel so much!
This I'm recommending because I adored it, but a lot, lot of people didn't, and I completely understand why: Que Sera, Sera. It's a bit of an older drama, but I loved its grittiness. The romance was so intense it was probably the sexiest drama I've seen :p But the characters spend a good part of the drama harming each other, so if that kind of thing gets on your nerves (I think I Miss You is kind of like that though, no? I haven't watched it)... The setup may be a bit typical (playboy + naive girl) but the characters are quite extreme and evolve a lot, which makes them very real -- apart from that, I don't think there's anything predictable about this drama at all. I had watched quite a few dramas once I came around to Que Sera Sera, and yet I remember not believing what was happening on my screen ;) Gasping and all, even though I'm normally a remarkably silent watcher hehe.
I personally disliked it, but a huge majority of people did love it, especially those that liked City Hunter: Bridal Mask (objectively speaking though, almost everybody admitted the romance was meh)
Good luck!
