Without giving away any spoilers, let me say one thing about Avengers Infinity War. To understand the movie, causal movie goers who dont know about marvel cinematic universe need to go through atleast 5-10 movies(either watch them or read their story and characters) in advance: The most important movies that they need to watch or know are: Captain America: The First Avenger, Iron Man-1, Avengers-1, Black Panther, Thor Ragnarok, Guardians of Galaxy-1 and Captain America Civil War.
Coming to the movie, let me go through the plus and minuses of the movie:
Plus points:
Best opening sequence which sets up the rest of the movie perfectly and what to expect. The almost silent BGM of the Marvel Studio logo animation means something really bad is happening and the mood in the theater is intense. The opening scenes were also shot very well and sets up the mood for the rest of the movie.
Crisp editing: At no point of time does it look like a 2hr 40 min movie. It looks as short as most hollywood movies. We may feel like it is just 2 hours because of intelligent editing and cuts. After the movie, we would actually want to wait for some more time to see what happens next.
Humour is put into the movie at the right moment without irritating the viewers. It makes the mood lighter.
The story and the way all the characters are linked is amazing to say the least. The biggest superheroes of this movie are not those we see on the screen but those behind it: The writers and directors who handled such a huge cast and never compromised on their screen time. Not even one minor character is wasted.
Climax: Though this could be controversial for marvel fans, it sets up the stage for the sequel coming up next year(2019). The tragedy is shown in a very heart touching way without being gory. The whole movie is very clean and perfect for all ages.
Minuses:
The audience need to be familiar with the marvel heroes/villains for the past 10 years.
Sometimes the pace looks slightly stretched with nothing much happening. Some comedy scenes could have been trimmed, but that is upto the editors to decide.
No valkyrie(for those who have seen Thor Ragnarok), and some other points were missed out as well.