The fact that every movie maker hopes to make an epic movie and in maybe 99% of cases the end result isn't an epic movie should tell you something.
Even Nolans strike rate is well below 25%
It the same as if Peter Jackson said he was going to make God of War, Joe Abercrombie's First Law trilogy, etc.....I would go in hoping/expecting something epic.
I don't think it's unreasonable to expect Nolan+The Odyssey to be epic.
Either way, it's all subjective.