The Agent character
I think the movie mostly depends on being a Beatles fan. If you're not, it might be tough going.
But one aspect that's interesting even for non-fans is the cynical agent character. She's horrible, but knows she's horrible, is fine with it and freely admits it to everyone. Maybe not so surprising a take -- the secretly nasty agent has been done so many times before -- but it's interesting to see how some parts of the biz work from the inside.