I am the kind of person who enjoys “big weird” scifi like Stanisław Lem. Stories about trying to relate to and find common ground with something so alien that the prospect of even understanding is basically hopeless. Star Trek usually doesn’t do stories that, which makes sense as it often uses alien races as allegories or stand-ins for real-world human relations.
That said- I thought those early Klingons were super weird and scary because they were just so alien. It really made sense thinking about how it took a century before they could get to the events of Star Trek VI, and it made the Khittomer accords feel like so much more of an accomplishment. Like- you made a treaty with WHAT?
And just aesthetically their ships and armor looked like something out of HP Lovecraft or HR Geiger:
This is not to say I dislike how Klingons were portrayed previously, kinda like Mongols in TOS or Vikings in DS9, just that they never felt scary to me. They never felt like warriors. I was never afraid for the gallant crew of the Enterprise D (a science and exploration vessel) going into battle against Klingons. But I really enjoyed the alien-ness Disco tried to go with. Anyone else with me?
EDIT: PEOPLE I SAID WHO’S WITH ME NOT WHO ISN’T CM’ON 
That’s the attitude of someone who does not really care about a continuous universe or a coherent world and just wants to watch sci-fi for the plot. If that’s the case, why not write and direct original fiction?
My entire enjoyment of Star Trek comes from the fact that it is a vast, largely consistent universe that feels real to me. I could mostly not care less about plot points or individual lead characters, I want the world that I know and love to expand. It’s like daydreaming.
Then I think you just want a totally different thing from star trek than me. imo Star Trek has always contradicted itself a lot, and I’m much more interested in the stories and characters, and I’m fine with the world being somewhat vaguely defined. There are so many things that don’t really make sense that people just gloss over, like Balance of Terror claiming that Romulans somehow have an empire in the 23rd century without having warp drive. Star Trek has been retconning stuff so much since it started that it’s weird to me for people to suddenly start caring about it when Discovery came out.