It being a "shared universe" had me going in a bit nitpicky on the details. If it were on its own, it would hardly matter but watching this with the concept of being connected to the original in mind, it's hard not to look at it closely hoping it doesn't contradict or devalue anything from the original. I'm surprised to say there's a shocking amount of consistency throughout in even minor details. For example, seeing the task force only form 4 months after the 'invasion' had me raising an eyebrow, but it quickly explained why they formed earlier there in Korea.
I still don't really know how to feel about the explanation for the protagonist's 'mutation' however. While it is a bit fresh (not even the spin-off manga tried that idea) it does feel a bit more superficial I guess? Fantasy-like? Consuming like half the brain and then moving over to the body a bit... I don't know, it just feels like it lacks the sense of cost that others have (having a body part other than the brain being consumed, being that you technically lost that body part in exchange for coexisting with that parasite). In comparison to other hybrid depictions, the circumstances here feel a bit too unrealistic, like a free superpower akin to Venom or something. But again, switching consciousness is an idea fresh for the series. So I have mixed feelings here.

Also this is probably because it's a drama, but the physical abilities of the parasites are definitely downgraded. Having normal humans dodge strikes from these creatures is completely contradictory to their ability. Their lightning fast speed is what made them such a convincingly huge threat to the human species, as practically any one-on-one encounter is literally hopeless for a normal human, being killed before they're even aware of it. But, for a series that focuses so much on human characters, having such overpowered creatures can definitely be difficult, not to mention making typical "on the edge" action scenes with them. So you're going to see a lot of missed strikes and just parasites slapping people around instead of going for the accurate insta-kill strikes like they're originally written. Like I said, I'm abnormally more nitpicky on this series because of its circumstances of being in the same universe, it probably doesn't matter that much but still it does bother me a bit.

There wasn't much discussion in the series as I'd like. Discussion about human values, philosophical ponders of survival, etc; all of it was really few and far between, forefronting the action plotline instead. I did like the little bit there was, and characterizing details like watching the certain parasites learn and develop in their own ways. But I really did want more from it in that regard, in the end most of it ended up being a cop thriller; sidelining character-driven storytelling.
The special effects weren't out of place at all, and looked impressive for how frequent they showed up. Actually, that's a big commendment right there- Lots of showcasing the parasites throughout the runtime of the series. Most television series try to sprinkle in the special effects scenes due to the budget, but this one definitely had enough to get the audience constantly familiar with these grotesque looking creatures.
The way it ended was cool in and of itself, but it does make you question where it will go with the series on it, if it does in fact get renewed for a second season. By large it was an entertaining little show. It wasn't all just action, it had lots of hints of a really good story and theme to go by, which is enough storytelling for those interested in the IP at least. Hopefully the second season goes for a less thriller movie-like approach and slows down a bit to be a bit more meaningful like the original manga.