Thanos just steals this show. I really like when villain is driven by something more than basic desire of "ruling the entire universe". The fact that his goal is somewhat honorable (even if ways are not so much) makes him even more fascinating character and creates conflict within the soul of a viewer. His ruthlessness and pure "don't give a shit" attitude in collecting Stones is really something to admire. Also, I'm kinda surprised he had to collect all of the Stones in one movie. I thought he was supposed to be background villain of MCU who collected these Stones throughout all of 20+ Marvel movies
Yeah, the ending. I guess, people turning in dust instead of melting alive or exploding from inside with a tone of gore is something you just have to do when your movie is PG-13. But I think it was used quite effectively and it just isn't a visual we get to see in movies much. Also, the fact that protagonists just lose and final shot of the movie is villain with a smile of satisfaction is pretty balsy choice in my book. I know that they all come back in Endgame and Thanos eventually loses, but I just don't care and appreciate quite dark ending of Infinity War.
... but they spared Cap, Iron Man and Thor
Also, I applaud to the person who was smart enough to
not put some stupid cheerful music in credits - it was perfect final nail, it was a statement: "yes, we wiped half of the universe and we gonna end our movie on that note". It's a problem I have with Star Wars movies - someone just decided that every Star Wars movie just has to start and end with the exact same music. When ending is supposed to be grim and depresing it just doesn't work when it's immediatly followed with jolly as f**k score. The same goes for Predators. Why, oh why you put Long Tall Sally in the end of Predators? It isn't even part of the movie score - it's just exploitation of nostalgia and it even wasn't done right