Poetic. Exhusating. Harrowing. Mournful. Perfect. You are not ready. Consider the bar raised.

Rating: 9/10 (26 April 2018)

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Surpassed all expectation; leaves you in mourning after the passing of beloved heros, while still hopeful and excited for what comes next.
This is quite simply not like anything you have ever experienced in the cinema. With undertones based around overpopulation, genocide and love; nothing can prepare you for the journey this will take you on. This is a movie that subverts expectation of any generic movie tropes you've come to expect from the genre; any issues can be understood and/or explained; Avengers 4 is almost impossible to predict following the events of Infinity war.
The most notable feeling from the film is the complete harrowing silence and loneliness felt in the final chapters minutes of the film; 18 films of backstory have led to this moment.
I have read reviews calling out the following points:

Lack of character development

We live in a world where the 18 other movies exist. This is part of a larger story arc and must be reviewed and objectively appreciated as such; you wouldn't say a book lacks explanation of the prior 18 in a series. This is a common critic problem, watch the previous films; it is common sense.

The black order lack of development

I don't personally feel character development makes sense in this film. Subtle developments are seen through out, this is a journey built around chaos. The lack of understanding of the group and quickness of events occuring is exactly what is needed. The characters in the story are outwit, outsmarted and caught completely off guard by the events of the film.
The lack of development is a bonus, it is a realistic representation of what happens in life. Make no mistake, this is a Thanos story; to review it as something less than what it has earned because it subverts and doesn't match the expectation of the audience theories or ideas is senseless and lacks understanding of the bigger picture.

The film moves around to much

I can say 100% after seeing this, the scenes were clear, present and relevent; nothing is vague or hard to grasp or follow. If you are watching the film, there should be no issues; the pacing is brilliant, bringing a larger than expected amount of slow and personal points where you would expect giant set pieces.
All in all, this is a near perfect film. With any issues being trivial or meaningless and understandable given the scale. Are things missing ? Yes. Is it understandable why - given the larger picture - these were replaced by more important story points, yes it is.
Would I like to see a longer cut, given we know there will be a large amount of deleted scenes? Yes. However, I can understand the priority given to the story and ensuring the most relevent points are made in the 2 hour 49 minute mandate.
Well done to Marvel and the Russo brothers. These film stands apart not only from the comic book genre, but films in general as something special, bewildering, exhuasting, tense, sorrowful but light hearted at the right points.
Consider the bar for comic book films raised. This IS the best comic book film. Period. For all that comic book films do; the film ends up in a place that's unexpectedly poetic and poignant, with some truly harrowing scenes.
Watch it without the backstory of the universe and it falls apart, but lets be realistic; they exist, lets stop ignoring the universe when everything special about this relies on the hard work that has gone into moulding the telling the previous stories.