It's not awful.
Ben Mendelsohn is pretty good and Samuel L. Jackson is funny as hell. The story is fine and the nostalgia is very appealing.
Brie Larsen just comes up very short.
She's wooden, fails in her comedy and just isn't believable as a badass. Her relationship with Maria is somewhere between just okay and forced.
The film is handicapped by a miscast lead.
My 12 year old daughter thought it was alright. She loved Wonder Woman. I'm sorry but there's just something to that.