I disagree about Triangle's ending being bad. Just because 'that' particular thing happened doesn't make it bad or that it ruined the story. The ending was bitter-sweet but I really love all the twist on the drama.
Tbh... I'd say that attention this series received was overhyped. The series? Not really. Sure... the fact that Sijin was nearly invincible with all the near deaths he's got as well as his and Daeyoung magical survival near the end might be too much to handle for some, but I don't see it being so bad. Tell the truth if we had bad endings of either one or both of them dying or any of the girls dying due to grief, there would still people complaining about wanting a happy endings. You can't please everyone. At least the writer didn't pull an ending like Lovers in Paris.
That said, DOTS was quite a refreshing story to me still. Aside from the fact it's a love story involving a pair of soldiers of different ranks as well as a doctor-soldier pair; this show had the male lead being the one struggling to get the female lead to return their feelings instead of the other way around, like how most Kdrama do. And this drama also had another female lead being the one who was considered 'elite' (Myeongju) --not the guy--who tried to hook up with a guy who was of lower military rank than her. And instead of the usual 'evil' mother characters trying to break a couple... it's a father. I can list more... but nah.
As for the plot... while some parts did have some flaws et al, but in the great scheme of things it's not really that big an issue. I've seen far worse dramas botching a potential interesting plot yet there's still people claiming that the show did well. Just because the leads were their biases. And what drama DON'T have mistakes? The show did cover the military part and doctors without borders part well... and they also managed to balance the serious and comedic part. Rather than trying so hard to focus on the too much hype, better to just enjoy it as it is.
K-Drama 
That said, DOTS was quite a refreshing story to me still. Aside from the fact it's a love story involving a pair of soldiers of different ranks as well as a doctor-soldier pair; this show had the male lead being the one struggling to get the female lead to return their feelings instead of the other way around, like how most Kdrama do. And this drama also had another female lead being the one who was considered 'elite' (Myeongju) --not the guy--who tried to hook up with a guy who was of lower military rank than her. And instead of the usual 'evil' mother characters trying to break a couple... it's a father. I can list more... but nah.
As for the plot... while some parts did have some flaws et al, but in the great scheme of things it's not really that big an issue. I've seen far worse dramas botching a potential interesting plot yet there's still people claiming that the show did well. Just because the leads were their biases. And what drama DON'T have mistakes? The show did cover the military part and doctors without borders part well... and they also managed to balance the serious and comedic part. Rather than trying so hard to focus on the too much hype, better to just enjoy it as it is.