Potential vague spoilers
Just watched it - probably the worst Marvel film and definitely the least interesting character. The film hasn't really got its own identity, steals vastly from the Guardians approach, doesn't really feel like a hero film and not in a good way. The villain of the film is essentially the comedic relief, which is actually its strongest point with some hilarious moments. Months of Feige saying she's the strongest hero feels like a lie, nothing really demonstrated that. Her powers aren't really well defined and her character is flat. Her main motivation is just that she can do things even with people saying she can't, it's essentially the marketing but lite. It's a feminist film, which isn't what makes it bad, what makes it bad is that it has nothing to say other than she's a female superhero and can do just as anyone else can. If you take that away what is she? Not too sure, seemingly not much.
Definitely didn't feel like a film that needed to be added before Infinity War. Fury, altohugh funny, has I think had his entire MCU's character destroyed. Overall I think if people will be honest to themselves after seeing it, it's a light-hearted easy going movie, but ultimately doesn't hold up to the rest of MCU's lineup and doesn't coincide with the established Avengers and the stage of where they are going into End Game.
Edit:
Other thoughts:
Half the action was great and gripping, the other half was poorly edited and up close, couldn't really see much of what was going on regarding hand to hand fighting.
This doesn't need to be watched before End War. The only link it has is the pager, this was an extremely strategically placed film.
Spoiler:
I saw the film yesterday and I absolutely loved it. 
