Let's get things clear from the gate: Train to Busan does nothing especially innovative to a densely crowded zombie genre. The plot revolves around a large group of survivors fleeing an infected metro area on a train that leaves the city. In that sense, it's basically Zombies on a Train. Much of the dialogue is cliche, the characters do a lot of dumb and unrealistic stuff, and there are several groan moments of over-emo scenes that Asians love to put on the screen.
That said, it's one of the most well shot horror films in recent memory. The cinematography is top tier, highlighted by a claustrophobic feel in many of its most intense moments. The characters are well developed-if not very familiar-which contributes to the audience being invested in the ride.
For me, this is by far the best movie in the Star Wars franchise. The characters are cool and believable, the action while predictable is top tier, the story arc keeps you ready to see what happens next. It's so amazing to me how bad of a job they did with Episodes 1-3 in the 2000s. This universe has so much going for it. I hope they can keep the small streak going.