Prefacing this by saying that I watched this with 0 subs of anykind, though I was able to understand ~70% of the words alone (intuition fills the gaps).

Star no Koi was genuinely an amazing watch, a true diamond in the rough, nearly everything about it was unique about it for the time and even now (especially the camera work, very similar to IWGP) and was on track to getting a 9.5 (10 is reserved in my rating scheme) all the way until the final ~4 episodes.

The story was genuinely interesting through and through, I REALLY liked how Sosuke's work life wasn't immediately cast to the background in favour of the more "special" person (we see this all the time, the higher profile person gets more screen time for their profession, which in turn makes it less "special") and despite it being so average of a job, it was genuinely interesting, same can be said for his workmates who had depth.
This isn't to say Hikaruko's work lacked depth, her profession was equally televised and people like her bodyguard had good character depth.
The thing that immediately caught my eye though was the camera work. Out of all the J-Drama and other Asian dramas I've seen, only ONE, has had a similar out of the ordinary camera work (previously mentioned IWGP) that really added life and uniqueness to the entire experience.

Now for the thing I disliked: the unexplained drama. As far as I know this could be just a discrepancy in my Japanese knowledge, but I really doubt that. First we have the mandatory love triangle, in anime I'm fine with that, not live action, partly because it's more unrealistic, but mainly because it's hardly done right, and this is no exception. Tsubomi all of a sudden fears competition and decides to really pursuit Sosuke after being in the company for x amount of years, yeah ok, and naturally of course she has to state the obvious that suddenly makes the ML reconsider and allow the way for more drama to ensue. Because I'm so used to this trope by now it alone doesn't bother me, but this time it did because of the fact that Sosuke SITS on that fact and misses signals that are more blinding than staring at a solar eclipse, and when practically confronted with it, he somehow manages to gaslight himself into believing otherwise. Doing this made it so painfully obvious they had to pad for time, especially considering this all occurred 2 episodes before the finale. Update after finishing the show: Yeah got even more annoying in the final 2 episodes, because both reasons are related to the climax I won't spoil it, but this one more happening alone dropped its score even more.

Regardless of that, I still think this is a 8.5, the technical aspects of the show saved it (music, top tier acting, camera work, etc.) Along with my general interest in it prior to the final arc and the genuinely funny comedic moments throughout.
If you can understand Japanese then I 100% recommend this show to you.