The Sign was a pleasant surprise for me when I first started watching it. It's a tad rushed in the second half but I still love it and I'm hoping more of the past lives/ mythology side gets explored in the special episode or if we get a second season (and I'd love a second season).
180 Degree Longitude Passes Through Us - IMO one of those "must watch" dramas. It's incredable.
7 Days Before Valentine Rated way, way too low at 7.1 (same director as 180 Degrees) . Patrick Rangsimant, the author who the novel is adapted from also had a couple of upcoming dramas including Mystique in the Mirror and I Love / Kill You
Not Me very very interesting plotline especially if you like political/ social issues
Midnight Museum not technically a BL but hinted and the plot is interesting (I'd love more of these supernatural themed stories like this and The Sign)
Shadow again not really a BL bot very interesting and it reminds me of a Taiwanese drama I really enjoyed called Detention.
To Sir, With Love very, very much a lakorn as it's just so over the top and ridiculous at times (which I completely love about it). Not for everyone
I don't tend to watch BLs where romance is the main focus (nothing wrong with them, just not for me). Aside from that as a former c-drama watcher I'd say censored danmei adaptions like The Untamed, The Spirealm, Guardian and Winter Begonia are worth a look if you're ok with a strong bromance alluding to romance with a darn good story.