Not that bad
I didn't think this was that bad. Kind of an average sci-fi/fantasy film, maybe slightly above average. I thought the effects were really well done, story was meh with a hollow villain, but the steampunk world they created was quite interesting. The soundtrack was probably the best part of the film. It might be worth picking up the book.
I get that the premise is absolutely ludicrous, but I think you would need to accept that going in. I think if you are going to apply this to any type of realism or physics you will hate this film, but it's sci-fi/fantasy so I'm not sure why people would have that expectation or why it's one of the main complaints about the film. It's like going to watch a superhero movie and then complaining that the protagonist has superpowers which isn't realistic.
Anyway, I would give it a 6/10.